Environmental Benefits of Natural Gas Vehicles
Energy security, fuel diversity, reduced emissions, and lower long-term costs are reasons why encouraging greater use of natural gas as a transportation fuel is a smart choice for fleets and consumers. The U.S. is the world’s top producer of natural gas and given this abundance, it will soon be a net exporter, helping other countries increase their energy security. It makes sense to build on the many benefits that this domestic resource provides by expanding its use in transportation. The transportation sector is heavily reliant on petroleum fuels and with respect to heavy duty applications, there are few viable alternatives to power fleets other than natural gas.
Natural gas facts with regard to emissions include:
Natural gas reduces tailpipe carbon dioxide (CO2) emissions relative to gasoline and diesel fuel by 26 – 27%, respectively, simply because it is less carbon intensive than gasoline and diesel. Natural gas consists mostly of methane (CH4) with a chemical makeup that is 4:1 hydrogen to carbon (gasoline has 8 carbon atoms and diesel has 16).
On a well-to-wheels basis (WTW), natural gas reduces overall GHG emissions by 11 to 17% compared to diesel or gasoline (see below).
Today’s natural gas engines emit significantly less particulate matter and nitrogen oxides (NOx) than engines produced just a few years ago. New low-NOx natural gas engines reduce ozone-forming NOx emissions 90% lower than the current EPA standard.
Renewable natural gas (RNG) is increasingly being used by fleets who wish to reduce their emissions even further. RNG is produced by landfills, waste-water treatment facilities, and through animal and crop waste systems. RNG is classified by the EPA as an advanced biofuel and a cellulosic biofuel under the Renewable Fuel Standard. RNG can reduce WTW GHG emissions by as much as 80 – 115% depending on the source compared to petroleum fuels.
Well-to-wheels comparisons of emissions related to natural gas versus gasoline and diesel vehicles can produce varying results given a variety of complex factors, including assumptions concerning upstream methane emissions and fuel efficiency of the particular vehicles being considered. WTW analysis indicates that NGVs, when fueled with conventional compressed natural gas, provide a 17% reduction in greenhouse gases compared to diesel fueled vehicles (assumes 25 GWP factor for methane, 100-year time-frame, 7% fuel economy penalty for natural gas).
Recent studies and analysis suggest that additional reductions from the natural gas system can be cost effectively implemented and that much of the emissions that is occurring is the result of super emitters or outlier sources. EPA has a number of new regulatory requirements that will also further reduce upstream natural gas emissions.
New technologies and innovation are also bringing advancements in natural gas engines. Cummins Westport is installing closed-crank cases on newer model year engines which will further reduce vehicle methane emissions by 70%. NGVs operating in Europe already use this technology and it is expected to be adapted to most heavy duty natural gas engines in the near future. Manufacturers of light duty natural gas vehicles can further reduce GHG emissions by taking advantage of natural gas’s near 130 octane rating and optimizing engines to fully benefit from these properties. Optimized natural gas engines could provide efficiency advantages that exceed gasoline and even diesel engines in the
As mentioned earlier, renewable natural gas (RNG) is growing in the NGV marketplace. Today, it is estimated that 20% of all natural gas used for on-road transportation fuel is RNG. Based on this estimate, natural gas used in transportation is already providing an overall reduction in GHG emissions by about 30% (assumes CA LCFS LFG CI numbers, 7% fuel economy penalty, and 100-year GWP time frame).
Natural Gas Vehicles Deliver Reduced Emissions for Fleets and Consumers
Today’s natural gas vehicles fueled by conventional natural gas deliver between 11 and 17% lower GHG emissions than similar diesel and gasoline powered vehicles.
Considering that 20% of the fuel used in natural gas vehicles is renewable natural gas, this benefit grows to 30%.
Future efforts to optimize natural gas engines and vehicles will increase efficiency and deliver additional emission reductions by taking advantage of natural gas’s superior attributes.
Medium and heavy duty natural gas vehicles will provide the most significant benefits because solutions are available today to address greenhouse gas emissions in a market segment where few other options exists.
Increasing the use of natural gas vehicles will help the U.S. meet its commitments under COP21, including achieving greenhouse gas emission reductions of 26-28% below the 2005 level in 2025.
Renewable natural gas provides a pathway to significantly greater emissions offsets. Today, fleets already have the option of contracting to displace a portion of the conventional natural gas they use, or they can go 100 percent renewable natural gas. Fleets using 100 percent RNG can offset greenhouse gas emissions by 80 – 115%.
The Benefits and Opportunity of Natural Gas Vehicles
As the largest producer of natural gas in the world, there is a tremendous opportunity today for the United States to use this key domestic energy source as a transportation fuel. Natural gas is an inherently clean-burning fuel that is helping fleets across the country lower their bottom line and achieve their sustainability goals. Recent announcements in the marine, rail, and heavy machinery sectors indicate they are now transitioning to natural gas as well. The expanded use of natural gas as a transportation fuel also holds a number of important policy benefits. With 33 states producing America’s abundant natural gas, extending the use of this key energy source is important to each state’s economy, air quality, and energy security. States can play an important role in promoting the use of natural gas for transportation and in growing the marketplace for natural gas vehicles (NGVs).
Transportation fuel consumption in the U.S. equals 66 Bcf/day, representing a tremendous opportunity for natural gas to displace a percentage of diesel and gasoline. Current growth areas for NGVs include the heavy duty regional trucking, refuse, transit, the medium duty package delivery and service markets, and oil & gas operations. Heavy duty long haul trucking, marine, rail, and heavy machinery are beginning to gain momentum and represents an even greater opportunity for reduced costs and emissions.
The natural gas shale revolution has dramatically changed the U.S.’s world position and enabled the U.S. to become the world’s top natural gas producer. Supplies of natural gas are at record high levels, and the Potential Gas Committee’s (PGC) most recently estimated supplies at 2,853 Tcf. This means there is a 90 plus year supply of natural gas that continues to grow. More than two thirds of the U.S. States supply this abundance.
Natural gas is an odorless, colorless, non-toxic, and non-corrosive source of energy that is abundant and produced in the U.S. When used as a fuel for vehicles it is cost effective, clean, and quiet, providing an excellent alternative to gasoline and diesel. Natural gas is used as a vehicle fuel in two forms, compressed natural gas (CNG) and liquefied natural gas (LNG). Increasing the use of domestic natural gas for transportation provides economic benefits and improves our energy security by displacing demand for imported oil.
Natural gas is not tied to world oil prices, creating a low-cost advantage that will last for decades to come.
Recently, CNG and LNG cost approximately $1.50 to $2.00 less than gasoline and diesel, although this difference is currently averaging about $0.40 - $0.75 less than diesel fuel.
The commodity cost of natural gas as a percent of the total delivered fuel cost is much less than for gasoline or diesel, providing stability in the total fuel price for CNG and LNG.
The incremental prices for NGVs and conversions are decreasing, and innovations in CNG and LNG fuel tanks will help to lower these costs further.
Natural gas consists primarily of methane (CH₄) and burns almost completely.
NGVs generally emit 11–17 percent fewer greenhouse gas (GHG) emissions than comparable gasoline and diesel vehicles on a well-to-wheels basis.
When replacing older trucks and heavy duty vehicles:
Nitrogen oxides (NOx) emissions are reduced 75–95 percent; and
Particulate matter (PM10) is reduced 95 percent for engines prior to 2007.
Natural gas is lighter than air and so rises and disperses quickly and does not damage surrounding ecosystems and water systems if vented.
New natural gas heavy duty engines produce NOx at levels approaching zero emission vehicles.
NGVs are 80–90 percent quieter than comparable diesel vehicles.
NGVs meet or exceed EPA standards for GHG and air quality.
Success Factors for NGV Market Growth
Many factors are involved in growing the NGV market, but key components are vehicle availability, fueling stations and government incentive programs. There are many options in the medium and heavy duty vehicle market for CNG and LNG vehicles, but each carries an incremental cost that must be overcome.
Over the past two years, fueling stations for CNG and LNG have grown 17%. This station growth continues due to the demand for NGV fueling is growing. More stations and vehicles per stations are needed, however, for a vibrant NGV market.
What States Can Do to Grow the NGV Marketplace
While natural gas is more cost effective than most other transportation fuels, the incremental cost of vehicle and costs to build stations are significant, justifying the need for incentives. Unfortunately, at the federal level only electric vehicles receive tax incentives. In many cases, states are stepping up to support the opportunity for NGVs by providing incentives. Needed policies that the states can provide include:
NGV grants and/or tax incentives;
Excise tax and method of sale based on gasoline and diesel gallon equivalent (GGE and DGE) units;
Incremental sales tax exemption—fleets should not have to pay more tax to buy a vehicle that is better for the environment than gasoline or diesel vehicles; and
Incremental weight exemption for heavy duty NGVs (add 2,000 lbs. to allowable limit).
The U.S. and its states are fortunate to have a vast natural gas resource. The natural gas industry provides jobs, revenue to land owners and governments, broad economic benefits to communities, and the investment of the industry’s employees in the state and their communities. The expanded use of this domestic resource will further aid states by reducing fueling costs and emission of harmful pollutants, and by providing greater energy security.
For more information, Contact:
Sherrie Merrow, NGVAmerica Chair, State Government Advocacy Committee, smerrow@NGVAmerica.org.
Jeff Clarke, NGVAmerica General Counsel & Dir. Regulatory Affairs, jclarke@NGVAmerica.org.
Make a Bold Impact on Air Quality Today
Allocating funds to deploy low-NOx natural gas vehicles provides the best way to deliver immediate and cost-effective NOx reductions and air quality benefit. Nearly 40% of Americans are exposed to unhealthful levels of ozone and particulate pollution. Volkswagen’s $2.9 billion Environmental Mitigation Trust fund provides each state an incredible opportunity to make an immediate and tangible impact on air quality by targeting medium- and heavy-duty vehicles, the leading source of these toxic air contaminants in almost every metropolitan area.
NVGs Offer the Cleanest Heavy-Duty Truck Engines in the World
Natural gas medium- and heavy-duty engines provide unmatched reductions of smog-forming emissions of nitrogen oxides (NOx). In 2015, a revolutionary natural gas engine was certified by the U.S. Environmental Protection Agency and California Air Resources Board to a level 90% below the EPA’s current exhaust standard and 90% below the cleanest diesel engine. A truck with this engine has an emission profile equivalent to that of a heavy-duty battery electric truck.
Dollar-for-Dollar, NGVs Deliver the Most Cost-Effective NOx Emissions Reductions
The calculations shown below assume the deployment of the cleanest commercially available model for each application. Funding natural gas vehicles will lead to the largest total reduction in NOx emissions.
NGVs are Commercially Available Today Across All Applications Qualified for Funding
NGVs are commercially available from traditional truck and bus OEMs with established sales and service networks. Retrofit and repower options are also available from a variety of manufacturers.
• Cement Mixer
• City Delivery Truck
• Conventional Van
• Dump Truck
• Fuel Truck
• Heavy Semi Tractor
• Large Walk In Van
• Motor Coach
• Rack Truck
• Refrigerated Van
• Refuse Truck
• Single Axle Van
• School Bus
• Shuttle Bus
• Transit Bus
• Tow Truck
• Utility Truck
Natural gas is a clean, low-cost, and domestically abundant transportation fuel.
Currently, natural gas prices can be $0.75 to $1 or more lower than diesel at the pump, with a firm price advantage expected to remain for decades as shown in the chart above.
Beyond the fuel-price differential, the pump price of natural gas remains relatively stable for two reasons. First,it is domestically sourced. Second, the commodity cost of natural gas only makes up 23% of the pump price so price fluctuations have minimal impact.
In contrast, approximately 60% of the price of diesel fuel is impacted by the market cost of crude oil, which is largely sourced from politically unstable, high-conflict regions. When crude oil prices increase, diesel prices follow suit which can lead to significant swings in a fleet’s fuel costs.
Volkswagen EMT Funding Recommendations
Fund alternative fuel vehicle projects that cost effectively maximize NOx reductions for both public and private fleets
Provide higher funding levels for medium and heavy-duty engines that deliver NOx reductions greater than current EPA standards
Target funding for technologies that have demonstrated lower in-use emissions
Prioritize funding for commercially available products and projects that are ready to begin
Stay flexible in plans and leverage private investment to stretch dollars and get more alternative vehicles on the road
Natural gas vehicles can fulfill all of these recommendations today!
For more information visit:


Not all of us have had the opportunity to work in a truly positive work environment. A positive work environment is important for the productivity of a company, but it is also important to us personally. Our emotional and physical health can be improved by working in a positive work environment. We should wake up each morning wanting to go to work – not trying to think of excuses to not go. We want to be proud of where we work and enjoy telling others about where we work. As an employee or a leader within a company you have a responsibility to create and maintain a positive work environment. Everyone has a responsibility to create and maintain a positive work environment. Even if this is not a company wide reality you can seek to provide this type of environment for your department/ division or those within your sphere of influence. This content will give you tools to be able to create the type of company environment that you crave through building and nurturing effective workplace relationships.
- Recognise what a positive workplace looks like
- Know and understand the key elements necessary to create and maintain a positive work environment
- Understand as an employee what you can to do personally to create and maintain a positive work environment
- Understand as a leader the responsibility you have to create and maintain a positive work environment
- Discover what type of team player you are and how that relates to your functioning in the team
- Know the importance of effective workplace relationships in creating and maintaining a positive work environment
- Know and understand the importance of working as a team and guidelines to good teamwork
- Discover your personal strengths and weaknesses in working cooperatively
- Discover your preference for dealing with workplace conflict
- Learn and practice various methods to deal with workplace problems
- Learn some of the common meeting problems to how make your meetings more positive and effective.


A NASA Earth Observatory image released December 5, 2012 shows the area near the Korean Peninsula on the night of September 24, 2012. The image was acquired by the Visible Infrared Imaging Radiometer Suite (VIIRS) on the Suomi NPP satellite. The image is based on data collected by the VIIRS "day-night band," which detects light in a range of wavelengths from green to near-infrared and uses filtering techniques to observe signals such as gas flares, auroras, wildfires, city lights, and reflected moonlight. The image has been brightened to make the city lights easier to distinguish. The wide-area image shows the Korean Peninsula, parts of China and Japan, the Yellow Sea, and the Sea of Japan.


Intraoperative hypotension (and to a lesser degree, hypertension) are very common issues which can occur in any case, so it’s important to have a methodical approach in diagnosing the etiology as well as treating it.
Let’s start with the basics – “blood pressure” (BP) conventionally refers to the pressure exerted by arterial blood on vessel walls. It’s the product of cardiac output (CO) and systemic vascular resistance (SVR). The vasculature (namely the arterioles) adjust SVR through vessel constriction or dilation based on autonomic nervous system regulation.
So BP = CO x SVR, and SVR accounts for 95% of impedence to blood ejection from the heart (“afterload”).
CO = HR x SV – Heart rate (HR) is affected not only by the rate but the cardiac rhythm. Stroke volume is a function of preload, cardiac contractility, and afterload based on the Frank-Starling law of the heart.
Pulse pressure (PP) is the difference between the systolic BP (SBP) and diastolic BP (DBP). A normal value is ~40 mm Hg. Narrow PPs could be due to aortic stenosis, coarctation, tension pneumothorax, or shock. Wide PPs can be from aortic regurgitation, atherosclerotic vessels, or high cardiac output states.
Mean arterial pressure (MAP) is roughly the average pressure during one cardiac cycle and is frequently used in the OR. MAP = 2/3(DBP) + 1/3(SBP)
- Noninvasive blood pressure (NIBP) cuff: an oscillometric BP determination as the cuff deflates. MAP is measured as the largest oscillation. SBP and DBP are calculated by proprietary algorithms.
- Invasive arterial blood pressure (IABP): cannulation of an artery (typically radial) with SBP, DBP, and MAP being accurately and continuously measured by a transducer
- Excessive anesthesia depth: overdose of induction agent, volatile, or narcotic
- Inadequate preload: hypovolemic shock, anemia, relative dehydration from fasting
- Increased intrathoracic pressure: high PEEP, high I:E ratio, pneumothorax
- Reduced afterload: vasodilated states like liver failure, sepsis, SIRS or depleted catecholamines from adrenal suppression, cocaine, amphetamines. Spinal anesthesia causes a sympathectomy thereby decreasing SVR.
- Other: acute MI, non-perfusing arrhythmias, cardiomyopathies, valvulopathies, pulmonary hypertension
Always start with an evaluation of five basic factors: preload, contractility, afterload, heart rate, heart rhythm.
Maybe the patient is too deeply anesthetized and I need to decrease the volatile agent? If preload is a concern, maybe a fluid bolus will help? Maybe a small dose of neosynephrine will help increase the afterload? Is the estimated blood loss (EBL) being replaced appropriately? Reevaluate the deficit, maintenance, and ongoing fluid losses – urine output and color can help gauge your repletion strategies. Transesophageal echo (TEE) can give valuable information about filling status, contractility, valvular disease, or effusions which may also be contributing. Auscultate the lungs, reduce PEEP, and shorten the ventilator inspiratory time if intrathoracic pressure is a concern. Double-check that electrolytes and acid-base equilibria are in check.
- Alpha-1 agonist => causes direct vasoconstriction
- Improves SVR but can cause reflex bradycardia
- Dose: 100 mcg IV q 2-3 minutes
- Indirect sympathomimetic (alpha-1, beta-1, and less so beta-2 receptor agonist)
- Causes the release of endogenous catecholamines causing an increase in HR, BP, and contractility. Consider conditions in which catecholamine stores may be exhausted if not responsive to ephedrine
- Clinically useful in patients who are vasodilated, bradycardic, and low output states
- Dose: 5-10 mg IV q 3-5 minutes
- The “big gun” pressor – direct sympathomimetic on alpha and beta receptors
- Used for acute, profound hypotension or refractory hypotension
- Increases vasoconstriction, HR, and SVR
- Dose: 10 mcg IV q 3-5 minutes – escalate from there
- Mechanism depends on the dose
- 0.5-2.0 mcg/kg/min => mesenteric, coronary, renal dilation (dopamine agonist)
- 2.0-10.0 mcg/kg/min => increased myocardial contractility and heart rate (beta-1 agonist)
- 10.0-20.0 mcg/kg/min => increased vasoconstriction (alpha-agonist)
Always keep adrenal suppression in the differential for hypotension (especially for those recently on steroids). A small dose of hydrocortisone can go a long way.
- Light anesthesia
- Chronic hypertension,
- Illicit drugs: cocaine, amphetamines
- Hypermetabolic state: malignant hyperthermia, thyrotoxicosis, neuroleptic malignant syndrome
- Increased intracranial pressure (ICP): Cushing’s triad – hypertension, bradycardia, and irregular respirations
- Autonomix hyperreflexia (spinal cord lesions above T5 are severe, lower than T10 are mild)
- Endocrine: pheochromocytoma, hyperaldosteronism
Just as with hypotension, the treatment for hypertension centers around temporizing the situation with fast onset, short-acting drugs and treating the underlying cause above all else.
If the patient is too lightly anesthetized, consider bolusing 10-20 mg propofol and cranking up the volatile (this may take longer to produce a result). If pain is the culprit, bolus 25-50 mcg fentanyl for additional analgesia. Beta blockers are always available (metoprolol, labetalol, esmolol) and vasodilators like hydralazine are often used for permissive hypotension to improve the surgical field and minimize blood loss.


Kieran Fenn fms
In the New Testament we find the start of Christian reflection on Mary – just the beginnings, not the fullness of Marian teaching and practice which has developed over the centuries.
The earliest reference to the mother of Jesus is found in Paul’s letter to the Galatians from the mid-50s: ‘But when the time had fully come, God sent forth his Son, born of a woman, born under the law.’ (Gal 4:4).
Little can be said for a Marian interpretation of this passage, but a basic affirmation is made: at the beginning of Jesus’ life there was a woman, his mother. Paul wants to show that Jesus was authentically Jewish and human as communicated through a Jewish mother.
The Christology of the passage is the profound centre of the statement; its message about Mary is limited to the fact that she is a woman and a mother. As early as this passage, a central point of Mariology is established: any truth about Mary is first of all a truth about her son.
But why her absence from the preaching of the apostles?
The apostles stick to the essentials. They were concerned to announce Christ, his passion and resurrection, his exaltation to God’s right hand and the salvation he brings.
Palestinian society was strongly patriarchal and it would not have been acceptable to speak of Mary.
The first generation had no idea of such issues as the virginal conception and assumption. The apostles knew only the adult Jesus, a prophet; they lived with him while he preached and worked miracles. They knew nothing of his childhood. Curiosity about his early life comes much later; the infancy narratives are the last part of the gospels to be written. The passion and resurrection are first.
The resurrection posed the question: ‘Who is this Jesus?’ The answer eventually takes two gospel writers back to his infancy, birth and conception and one to the pre-existence of the Word. In this context Mary was presented late in the development of the New Testament.
Mary in Mark
The mother of Jesus is in all four gospels, but they present quite distinct pictures reflecting diverse theologies of world history and understandings of Jesus and the needs of the local churches for which the evangelists wrote.
In Mark, we have just the faintest outline; Matthew gives a slightly stronger sketch; Luke and John provide a vivid painting or full-bodied sculpture of the woman disciple and mother. In no gospel is Mary the dominant figure; always she is presented as being in some relationship with her son. This is her role, not as an end herself, but as a pointer to her son. What is fascinating about Mary and her role in our salvation story is the significant development in the appreciation of her by the various gospel communities.
The temptation is often to bypass Mark and go to the more flattering texts. The earliest Christian tradition on Mary is the story of the visit of the mother and brothers (Mk 3:31 to 35). Unlike the more popular Marian texts, this seems to cast Mary in a negative light and embarrasses those who are devoted to her. If all we had was Mark’s gospel, we would have the name of the mother from 6:1-6a, two negative stories of rejection and no deep devotion to Mary as integral to Catholic Christianity.
What is Mark doing?
The gospels cover a passage of more than 60 years; earlier traditions are modified, and understood in a better way. The text on the family of Jesus asserts that it is open to every human being, a family not limited by blood, tribe, nation, colour or culture; in this family there is a place for each one.
And in this family, we could be mother, brother, sister for Jesus, (but not Father! 3:35). Mark’s primary intention is not to say anything about Mary, but to cast Jesus’ words in as strong a light as possible. This is best done by powerfully contrasting the two families.
Mary was probably not known to Mark and his community; with so few references it is unlikely Mary was a significant figure in the early Markan church. The main point is not that Jesus did not care for his mother, but that to belong to Jesus in relationship depends on the faith rather than on the blood connections of a disciple. Discipleship is the issue rather than affection for his mother.
The gospel’s perspective
In Mark’s gospel everybody fails Jesus – his disciples, his people, his family. He dies with that terrible cry of abandonment: ‘My God, my God, why have you forsaken me?’
We know this line from Psalm 22 which ends on a confident note; but let us not rush to that point until we recognise that in Mark, Jesus dies in utter desolation without any relieving features. Jesus’ isolation could go no further – deserted by his disciples, taunted by his enemies, derided by those crucified with him, misunderstood by his family, suffocating in the darkness of evil.
The worst is feeling abandoned on the cross, even by God. At least his mother and brothers are in good as well as bad company!
Mark’s second reference
Jesus’ unhappy return to his home town results in the villagers taking offence at him. It is said that he is son of Mary, brother to James, Joses, Judah, Simon, and his sisters are still there among the people.
The son of Mary seems too familiar to be of any religious significance for them. Sadly, the villagers ask the right question: ‘Where did this man come from or get all this learning?’ But they give the wrong answer. They think they know the source of his power and authority because they know his earthly origins. What they miss is the faith dimension that is part of being a disciple; it is not enough to know the son of God only as the son of Mary.
Augustine was to add an important comment to these Markan scenes when he reminded us that: ‘For Mary, it was a greater thing for her to have been Jesus’ disciple than to have been his mother.’
Discipleship is a matter of faith rather than the natural relationship of family, an important issue in those early days when becoming a Christian could and did lead to family division (see 13:12).
References: Maloney, FJ: Mary, Woman and Mother, and Brennan, W: The Sacred Memory of Mary.


In the case of friction piles, the load is acting downwards while frictional force to resist that load acts upward. That frictional force is called skin friction.
However, in cases when pile and a part of the soil in which the pile is there is settling. And if this settlement is more than the pile settlement, it will also apply downward frictional drag on the pile surface and the force arising on the pile surface due to negative frictional drag is called negative skin friction.
In such a case when loading is applied, there will be two forces acting downward: acting load and negative skin friction. Therefore part of the load-bearing capacity of due skin friction pile will be utilized to overcome negative skin friction and the rest would be available to resist the acting load.
Therefore, the load-bearing capacity of the pile is reduced. There are several reasons for soil settling more than the pile:
- If the settling layer is very compressible and when a little bit of loading on this soil is applied, it will settle more than the pile. Hence, negative skin friction will develop.
- If the settling layer is a recently filled soil, then over time its consolidation will take place. And because of this over time consolidation, negative skin friction will develop.
- A third reason is the effective stress increases.
As we know that the consolidation is a function of effective stress. Therefore, when effective stress increases then settlement will be more. As a result, negative skin friction will be developed. Change in affective stress happens when the water table rises or goes down.
The process of calculation of negative skin friction is similar to skin friction as shown earlier. However, it acts in a downward direction.


In our science unit on Simple Machines we are learning about different types of simple machines and how we use simple machines everyday. Students will be making a simple machine project for homework over the next two weeks. Please see the Simple Machine Project page. You can also visit my Pinterest Board http://www.pinterest.com/rendeez/simple-machine-projects/ to see some sample projects.
We also enjoyed some "our class alone" time on the new playground as a class reward on Wednesday.
Please look for book order forms in the Friday Folder. Use the code GQJD2 when you order to help benefit our classroom library. Students are always excited to receive books when the book box arrives.


1900 Yukon Nuggets
Frances Muncaster: Pioneer Woman of Squaw Creek
She was an American woman who gave up the life of high society, comfort and privilege to live the tough life of a miner in the wilds of the Yukon and northern British Columbia.
She was small and slim, with a beautiful oval face and engaging gaze. She was as comfortable in fashionable gowns as she was when attired in the rough and ready garb of the out of doors.
Arabelle Frances Patchen was born August tenth, eighteen seventy four (1874) in St. Paul, Minnesota . At age twelve, her family moved to Spokane, Washington. She was only eighteen years old when she married an older prosecuting attorney in Spokane and became “an ornament to Spokane society.”
The marriage only lasted three years, after which she married Thomas Noyes, the son of a Montana mining tycoon. They came north during the Klondike gold rush, ending up in Nome in nineteen hundred (1900).
They had varying success. At one time, Frances was the toast of Monte Carlo, but then the couple was wiped out financially. They tried their luck during the Chisana gold rush of nineteen fourteen (1914), in the south west Yukon, but failed.
Frances remained in Alaska after her husband’s death, managing a cannery store until she met and married Bill Muncaster, a surveyor who was fifteen (15) years her junior. Bill and Frances were made for the north. For their honeymoon, they spent the winter in a tiny log cabin on the shores of the Yukon’s remote Wellesley Lake in temperatures that dipped to fifty (50) below.
For years they continued their quest for gold in the south west Yukon. Then in nineteen twenty seven (1927), while visiting relatives in Seattle, they received word that Paddy Duncan had discovered gold on Squaw Creek, a tiny tributary of the Tatshenshini River.
They mined at Squaw Creek for the next twenty (20) years, making enough to carry them from one mining season to the next. Among her other duties, Frances was the mining recorder for the region, but as the years passed, her energy waned
She died of a heart attack in Haines, Alaska in 1952, after more than a half century of hardship and adventure in one of the most remote regions on the continent.
Frances Muncaster plotted her own course. Hers was a life of rebellion and adventure in which she overcame hardship in the wilderness that she loved.
A CKRW Yukon Nugget by Michael Gates.


16th century europe map. This was very much inspired by the rediscovery of ptolemys geographia. Published in sienna in 1600 this italian map shows the latest knowledge of the geography of europe. Countries are what count. A map of europe during the period of transition from medieval to modern history showing the political boundaries in the first half of the 16th century.
At a more local scale of analysis europe map the tendency is if anything more pronounced. History maps from the year 1501 1600 the sixteenth century. Media in category maps of 16th century europe the following 20 files are in this category out of 20 total. Online historical atlas showing a map of europe at the end of each century from year 1 to year 2000.
A map of europe in the 16th century. 16th century historical map archive sorted chronologically. In the public imagination to know the locations of the member states of the un is to have mastered world geography. 16th 17th century maps the awakening of interest in geography in europe started with the need to find new trade routes to the far east.
The writing is in italian and a dedication is given at upper left in a cartouche along with the name of the cartographer ar. Map of europe in the 16th century 1500 1599 from the maps web site. The 16th century is regarded by historians as the century in which the rise of the west occurred.


Explaining migraine pain itself is often very difficult. Migraine pain is very subjective and at this time we have no method of objectively measuring it. The pain that occurs during a migraine is whatever the person experiencing it says it is and that varies from individual to individual.
Cause (Oxidative Stress)
"Oxidative stress is essentially an imbalance between the production of free radicals and the ability of the body to counteract or detoxify their harmful effects through neutralization by antioxidants. Like an apple turns brown when exposed to air, our cells can "rust" when we breathe due to oxidative stress, a process caused by free radicals. Free radicals are unstable molecules that damage or "oxidize" cells throughout the body in a process called oxidative stress."
A recent study at the University of Maine concluded that oxidative stress "is a plausible unifying principle behind migraine triggers". Oxidative stress triggers "neurogenic inflammation."
The leading over-the-counter medicines like Excedrin, Motrin, Advil, Aleve and Tylenol contain acetaminophen, aspirin, naproxen and caffeine. They are nonsteroidal anti-inflammatory drugs that may offer some relief. Prescription drugs like Imitrex, Zomig, Ergomar and others are anticonvulsants, antidepressants, bata-blockers and antihistamines and while they may provide relief they all can cause serious side effects.
Drug treatment for migraine is used to block or reduce inflammation but side effects from drug use can be as debilitating as the symptom being treated. Nausea and vomiting are common others include dizziness, weakness, difficulty thinking, chest pain and constipation. Recently Botox has been used to treat migraine but it can cause serious side effects that can be life threatening.
Another problem with using drugs or overusing drugs to treat migraine is rebound headaches. According to the Mayo Clinic, "Rebound headaches (medication-overuse headaches) are caused by regular, long-term use of medication to treat headaches, such as migraine. Pain relievers offer relief for occasional headaches. Rebound headaches usually stop when you stop taking the pain medication
Based on the recent breakthrough identifying neurogenic inflammation as the result of oxidative stress it stands to reason that the first and best treatment for migraine is to reduce the inflammation. ICE DOWN cold therapy does just that. As a matter of fact the quicker your reaction time in applying ICE DOWN the quicker you can reduce pain.
How does ICE DOWN treat migraine? ICE DOWN draws the heat out. In other words it sets up a heat exchange pulling the heat out of the area of application thereby reducing inflammation. The benefits derived are an endorphin release, the body's natural opiates which reduce pain, a reduction of inflammation and vasoconstriction. The same as migraine drugs without side effects. No drug can cause the body to produce endorphins but ICE DOWN does.
Not only does the ICE DOWN migraine head wrap relieve, reduce or stop pain it often does so quite dramatically. There is clear evidence of the benefit and efficacy of ICE DOWN. Observations during the clinical study leave no doubt to the efficacy of ICE DOWN. It is highly effective in treating, relieving and reducing or stopping migraine pain.
The benefit derived from using I.C.E. DOWN to treat migraine is actually better than the leading drugs for the treatment of migraine. Like the drugs used for migraine treatment ICE DOWN reduces inflammation and causes vassal constriction with the added benefit of providing endorphin production. It is exactly the same as those provided by drugs but without side effects. It is 100% safe and effective and provides a life-long alternative to drugs with no side effects.


Toxic Dioxins Released in Air Risk Human Health and Reduce Crop Yields
Of the most polluted cities in the world, few stand so prominently as Delhi, India. In fact, the Indian capital — which is home to more than 7 million people — has gained notoriety as the “air pollution capital” of the world. Until recently, scientists have been puzzled as to why Delhi sees thicker smog than other cities with widespread pollution issues, like Beijing. But a new study published in Nature Geoscience has uncovered what is likely the x-factor: burning plastic waste.


5 Tips: How to Ensure Your Body Language is Creating a Positive Image
by Kay Hunter
Silent signals¦Understanding and using body language is a very useful skill in any business or social situation. Studies show that your actions speak much louder than your words. Words alone may not secure the truth or true feelings in any given conversation. Our bodies do not know how to lie.
1. Eye Contact – Your ability to make direct eye contact is critical to your professional and personal success. When you are meeting someone and shaking hands, eye contact should be maintained throughout the entire shake. You should know the color of their eyes when you are finished. At this point, your eyes should glance away for a moment. Staring someone down without ever moving your eyes will make people uncomfortable!
2. Facial Expressions – A warm smile invites conversation and openness. The key is the smile must be sincere, people can read a fake smile a mile away. When you want to show you are interested and listening, smile and nod your head up and down. Keep your hands away from your face when you speaking, because this gives the impression that you are unsure or lying!
3. Handshakes – The handshake is the focal point of the American greeting ritual, and it often determines the comfort level and success of an entire meeting. Start with direct eye contact, then initiate the shake (gender is not a consideration). This demonstrates confidence, professionalism and gracious behavior. Meet the person’s grip web to web and palm to palm. The shake should not be a bone crusher or wimp out with the two-knuckle finger wiggle (the kind of handshake that only includes half the hand). If you suffer from sweaty palms, blot your hand before shaking.
4. Body Posture – Stand with your weight equally distributed on both feet. This will eliminate the appearance of being bored or fatigued. When you lean, you lose 95% of your presence or authority. Proper posture communicates self-esteem – stand tall to portray confidence. Lean forward slightly to communicate interest, a bit further forward if you want to express pressure.
5. Gestures – Use “open” gestures, (i.e. hands at your sides vs. crossed over your chest) these will put your listeners at ease; you will appear open, honest and ready to listen. Avoid gestures that are distracting (i.e. clearing your throat, sniffing, playing with items in your pockets, touching your hair). These gestures communicate that you are uncomfortable, anxious or bored.
Are your Business Etiquette skills getting you ahead of the competition? Are you comfortable that you know how to conduct a proper introduction, or exchange a business card properly? Call now and sign up for a personal Business Etiquette session – 1 1/2 hrs.
Kay Hunter is a personal image coach and corporate trainer, specializing in complete makeovers, business and dining etiquette, and is the president of Imagine¦The Possibilities in Tustin. She has transformed hundreds of clients into more successful and confident professionals. Kay can be contacted at (714) 665-8866, email@example.com,www.kayhunter.info.


St. Patrick’s day is a holiday celebrated around the world with Irish music, whiskey, and lots of green. The holiday usually signals the imminent arrival of spring and is often celebrated raucously with parades and drunken bar crawls. However, many of the people who participate in the festivities of this holiday don’t even know how it originated. When asked, many revelers will say that its a holiday for an Irish Catholic guy and something to do with clovers and snakes.
“The modern celebration of St. Patrick’s Day really has almost nothing to do with the real man,”- Philip Freeman
Lets start at the top. St. Patrick himself was actually not Irish. He was actually born in Britain to a well-to-do Roman family. He was kidnapped at 16 and sold as a slave in Ireland, spending years tending sheep in the countryside. According to legend, he was converted to Christianity there and became a fervent believer. He heard a voice one night telling him to escape his slavery, he did, and returned to England where he was reunited with his family. He was ordained by a Bishop in Britain before returning to Ireland as a missionary. He died in Ireland on March 17, 461, after many trials and hardships during his missionary work. Although he was largely forgotten after his death, over time the mythology around him grew until he became the Patron Saint of Ireland in 600.
The overwhelming theme of St. Patrick’s day celebrations is the shamrock, as revelers wear them on their clothes and drown them in their beers. The four leaf clover is often seen as a good luck charm, as it is rare amongst the 3-leaf variety, but is not the true symbol of the day. According to legend, St. Patrick used the 3-leaf clover to teach about the Holy Trinity during his missionary work in Ireland. However there actually is no evidence of St. Patrick ever doing that. In fact, the wearing of clovers began in the 17th century as Irishmen and women wore shamrocks on their coats and placed it in their whiskey before drinking it at the end of the day. The wearing of the shamrock was a symbol of pride in their Irish heritage as the English began seizing land and ruling over the Irish people. Unfortunately, the shamrock is not a purely Irish plant, and can be found throughout Europe.
According to one legend St. Patrick stood atop a hill, now called Croagh Patrick, with only a wooden staff and banisned all the snakes from Ireland. Another says St. Patrick was fasting when he was attacked by snakes, so he chased them into the sea. Since snakes traditionally represent evil in religious texts, especially the bible, the story took root amongst new converts. And while it is true that there are no snakes on the island, there were never any to begin with. The Irish sea is much too cold for snakes to migrate from neighboring islands.
Leprechauns are figures from Celtic folklore. Celtic tales are full of tiny fairies with magical powers, that could choose whether to use their powers for good or evil. Leprechauns were represented as cranky fairies, tricksters and pranksters that were always out to protect their treasure. They were often shoemakers and cobblers, drinking and smoking and mending the shoes of other fairies. Today they are seen as drunken little men garbed in green with rosy red cheeks and bright red hair.
Corned Beef and Cabbage:
The classic St. Patrick’s Day meal is actually an American-made dish. Irish immigrants in New York City in the early 19th century were often poor. Corned beef was the most affordable meat available, and was substituted for Irish bacon which was much more expensive. Cabbage, on the other hand, has always been an Irish food, but again, more so because it is a cheap spring vegetable than for any religious or holiday significance.
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3 Answers | Add Yours
The genre of novel superceded the Romances, Chants, and the Epic stories of the 17th century by replacing the themes from historical realistic fiction, historical non-fiction, and chivalry romances with more fictional story lines that had not been seen before in English literacy.
The first novel accepted by theme and form would definitely be Robinson Crusoe as you stated. Previous to Crusoe, two more novels had been published but it was Crusoe which obtain the attention and the girth of importance that would be characteristic of the modernistic novel: One that comes with a fictional thematic narrative, detached from historical non-fiction, and categorized by ease of use.
Industrial Capitalism, Individualism and the Rise of the Novel
1-The rise of the novel during the eighteenth century is greatly associated with the rise of individualism at that time.
2- Individualism stressed the fact that every individual was independent from other individuals, and as a direct result of industrial capitalism, it emphasized that the individual had to choose and decide his future. Modern industrial capitalism, also, taught people how to earn money ,and how increase it. Thus it brought emphasis on the individual and his money.
3- In the past, characters in the romances stood for certain qualities(e.g. Mr. Greedy, Mr. Angry,…etc.) and not for themselves.
4-In the eighteenth -century novel, individual characters are drawn as independent regardless of their social status or personal capacity. They are portrayed as complex characters, affected by social pressures.
5-Eighteenth –century novelists such as S. Richardson, H. Fielding, and D. Defoe studied the individual’s attitudes, feelings, and motivations. Defoe emphasized individualism by writing a novel that has one central character with independent individual characteristics. Likewise, Richardson and Fielding concentrated on the individual and named their novels after their main characters.
6-The modern industrial capitalism made people pay great attention to money: how to gain it and how to keep it. In the earlier prose fiction, the main character had moral ideas, and thought only of virtues and good deeds. The eighteenth-century writers became more realistic and dealt with the only interest of the individual at their time, i.e. money. All Defoe’s characters pursue money, and they pursue it very methodically according to the loss and profit of book-keeping. Thus Robinson Crusoe leaves his father’s house and the secure life of the middle class to seek more money. This materialistic point of view began to have a tremendous influence to the extent that idealistic moral values were no longer the core of stories, but the individual and his struggle to gain money.
In a new foreword, W. B. Carnochan accounts for the increasing interest in the English novel, including the contributions that Ian Watt's study made to literary studies: his introduction of sociology and philosophy to traditional criticism. Praise for the new (2001) edition:
"Ian Watt's The Rise of the Novel still seems to me far and away the best book ever written on the early English novel—wise, humane, beautifully organized and expressed, one of the absolutely indispensable critical works in modern literary scholarship. And W. B. Carnochan's brilliant introduction does a wonderful job of showing how Watt's book came into being and changed for good the way the novel in general is taught and understood."—Max Byrd, author of Grant: A Novel
"Ian Watt's The Rise of the Novel remains the single indispensable, absolutely essential book for students of the 18th-century novel."—John Richetti, author of The English Novel in History: 1700-1780
Praise for the original edition:
"A remarkable book. . . . A pioneer work in the application of modern sociology to literature."—Manchester Guardian
"An outstanding contribution to the field of historical sociology and the sociology of knowledge. . . . The author has set the 'rise of the novel' as a new literary genre in the social context of eighteenth-century England, with emphasis on the predominant middle-class features of the period."—American Journal of Sociology
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2020 has been a hard year by anyone’s standards. So it’s almost as if the universe is offering us some magical karmic payback this month. Over the course of this month all seven planets will be visible from earth as they take their places next to one another!! What an amazing opportunity to get outside and soak in how truly small out problems are.
Venus Takes Center Stage
Venus will be the brightest this week. But we will be able to see Saturn, Jupiter and Mercury without a telescope or strong set of binoculars. To see Uranus or Neptune however you will need to use a tool for assistance.
As our solar system is aligning Venus is seemingly stealing the spotlight! This planet is going to be a striking sight in the morning sky and will remain visible for the rest of the year, according to Earth Sky.
Venus will share the morning sky with Mercury as it is visible in the Northern Hemisphere for the first weeks of November.
Curious star-gazers can use Venus to find Mercury. To do so, find the brightest ‘star’ in the sky and then look downwards. You should be able to notice Mercury towards the horizon.null
12 and 13 November will be especially great days for spotting these two planets.
The Rest Of The Starry Cast
Mars has actually been visible since the last bit of October and is easily spotted. If you find a bright star that has a reddish colour – that’s probably Mars.
Jupiter and Saturn are also visible all through the month as they come closer to their aligned spots.
This is something that happens for these two planets only every 20 years. To see them, keep an eye on the moon around 19 November.
Towards the end of the week, Uranus will be visible with a green-blue colour. You will likely get the best view of this planet at the beginning of November in the evening.
If you have a telescope or binoculars, you will be able to see Neptune at any time of the month, as long as you look at night.


The global health body says 21 deaths and 37 new suspected cases have made this outbreak one of the largest in 7 years, defying local claims that the virus is under control
Ebola cases have spiked in the west African nations of Guinea and Sierra Leone, according to new figures released by the World Health Organization on Wednesday, undermining local officials’ claims that the virus has been contained.
The outbreak caused a suspected 21 deaths and 37 infections in Guinea between May 29 and June 1. In the same period, Sierra Leone recorded 13 new cases.
The updated tally brings the total number of suspected cases to 328. Health officials have confirmed the presence of Ebola in 193 of the cases so far, making it one of the largest recorded outbreaks in seven years.
Ebola is a highly infectious haemorrhagic fever that can have up to 90% fatality rates.


This article by Rod Ellis is the first research intensive piece of writing, over 20 pages long, that I’ve read in less than two hours. “Current Issues in the Teaching of Grammar: An SLA Perspective” was really interesting, because it laid out the debate over teaching grammar in a clear, concise way, listing the evidence and the research that has been done to study all sides of the issue.
He discusses the issue of teaching grammar (which he defines as “any instructional technique that draws learners’ attention to some specific grammatical form in such a way that it helps them either to understand it metalinguistically and/or process it in comprehension and/or production so that they can internalize it” (p. 84)) in 8 separate questions: 1. Should grammar be taught? 2. What grammar should be taught? 3. Should grammar be taught at the beginning of instruction or after some level of competence is achieved? 4. Should grammar be taught in a mass or distributed over a longer period of time? 5. Should grammar be taught intensively (one structure at a time), or extensively (multiple structures at once, repeatedly)? 6. Is there any value in teaching explicit grammar knowledge? 7. Is there a best way to teach implicit grammar knowledge? 8. Should grammar be taught in separate lessons or integrated in with communicative activities?
In the article’s conclusion, Ellis delineates his own personal preferences to the questions he explores, but emphasizes the need for additional research done in all areas of teaching grammar, and that there are no clear-cut answers.
Ellis, Rod. “Current Issues in the Teaching of Grammar: An SLA Perspective.” TESOL Quarterly,
40.1 (2006): 83-107. http://www.jstor.org.mantis.csuchico.edu/stable/40264512


They say it is effective in a quarter of patients with a real risk of dying from coronavirus and could save hundreds of lives.
Two medications: tocilizumab and sarilumab, could reduce the risk of death in severe coronavirus patients. The negative is that cost of each of these substances is quite high. Together, however, they are cheaper than intensive care in hospitals or clinics.
The information on these two drugs comes from a group of UK scientists. The experts took into account the before and after figures they conducted the trials with these two drugs.
First, without tocilizumab and sarilumab, of 800 patients admitted to ICUs, one 36% died. While, after they started using the doses of drugs mentioned, the figure dropped to 27 percent.
« For every 12 patients you treat with these drugs, you would hope to save a life. It’s a big effect, » said Anthony Gordon, principal investigator of the Imperial College London, as published by the BBC.
Application and effect on coronavirus
The cited agency states that the administration of both drugs is drip. They also claim that it has an effect similar to that of dexamethasone.
« The fact that there is now another drug that can help reduce the mortality of covid-19 patients is very welcome news and another positive development in the ongoing fight against the virus, » celebrated Stephen Powis, NHS National Medical Director.
Health professionals explained that this drug stops inflammation that can accelerate in severe patients with coronavirus. Thus, damage to the lungs and other organs attacked by the virus is prevented.


1. What do you mean by accommodation of human eye?
2. Define power of accommodation of human eye and Calculate its value for a normal human eye.
3. Draw a neat labelled diagram of human eye and explain the function of each part.
4. What is Myopia? How is it caused? How can it be corrected? Explain with the help of a diagram.
5. What is hypermetropia? How is it caused? How can it be corrected? Explain with the help of a diagram.
6. What is presbiopia? How is it caused? How can it be corrected?
7. What is astigmatism? How can it be corrected?
8. What is dispersion?
9. Draw a neat diagram to show the dispersion of light when passed through a glass prism.
10. How is rainbow formed?
11. If you see a rainbow in the morning, in which direction of the sky will you see it?
12. What is scattering?
13. Explain the blue colour of sky?
14. Why clouds are white?
15. A red coloured piece of glass appears white when it is ground. Explain why?
16. What is Tyndal effect?
17. Write the constituent colours of white light in order of increasing wavelength.
18. When you enter a dark room from sunlight, you cannot see things for a while and after sometime you start seeing things. Explain this observation.
19. Why do stars twinkle?
20. Define near point and least distance of distinct vision. What is its value for a normal human eye?
21. Define far point. What is its value for a normal human eye?
22. Draw a neat labelled diagram showing the refraction of light through a glass prism.
23. The sun is seen a few minutes before actual sunrise and after actual sun set. Explain why?
24. The sky appears black when viewed from the surface of moon. Explain why?
25. Why danger signals are of Red colour?
26. Why sun appears reddish during sunrise and sunset?
27. The setting sun is more reddish than rising sun. Explain why?
28. What is persistence of vision? How does it help us in seeing motion pictures?
29. What are primary colors?
30. Why planets do not twinkle?
31. What is total internal reflection?
32. What is cataract? How is it corrected?
1. What is the least distance of distinct vision of a normal human eye ?
2. Name the muscle responsible for bringing change in the focal length of the eye lens ?
3. Name one defect of vision which cannot be corrected by any type of spectacle lenses ?
4. State one effect produced by the scattering of light by the atmosphere ?
5. What is the nature of image formed on the retina of the eye ?
6. What type of lens is used for correcting hypermetropia ?
7. Who was the first person to obtain the spectrum of sunlight ?
8. What is the function of optic nerve in human eye ?
9. What is range of vision ?
10. Why do different colours deviate through different angles on passing through a prism?
11. As light rays pass from air into glass prism, are they refracted towards or away from the normal ?
12. Which color has largest wavelength ?
13. Which defect of vision can be rectified using a concave lens ?
14. What phenomenon causes twinkling of star on a clear night ?
15. What is meant by scattering of light ?
16. Why does the sky appear black instead of blue to an astronaut?
17. What is the basic cause of atmospheric refraction?
18. Why does clear sky look blue?
19. Can visible light be scattered by atoms/molecules in earth’s atmosphere?
20. What is a spectrum?
21. Name the defect of vision in person
a. Whose near point is more than 25cm away?.
b. Whose far point is less than infinity.
ANSWERS OF THE ABOVE QUESTIONS :
Ans 1. 25cm.
Ans.2 Ciliary muscle.
Ans 3. Cataract.
Ans 4. Tyndall effect.
Ans.5 Real and inverted.
Ans.6 Convex lens.
Ans.7 Sir Isaac Newton.
Ans 8 Optic nerve carries the image formed on the retina to the brain in the form of electrical signals.
Ans 9 Range of vision of a normal human eye is between it’s near point and far point i.e, from 25cm to infinity.
Ans 10 This is because different colours travel through glass with different speeds and glass has different refractive index for different colours.
Ans 11. Towards the normal.
Ans. 12 Red color.
Ans. 13 Myopia.
Ans. 14 Atmospheric refraction.
Ans. 15 Change of direction of light on striking a scatterer.
Ans. 16 The upper atmosphere does not have particle or dust etc. as a result there
is no scattering of light and hence the sky appear dark in stead of blue to an astronaut.
Ans. 17 The basic cause of refraction is variation in optical density of different
layers of earth’s atmosphere. The sun passes through earth’s atmosphere.
Ans. 18 Because blue color having smallest wavelength is scattered most, Amount of scattering is directly proportional to 1/??4 .
Ans. 19 Yes, as size of molecules/atoms is much less then wavelength of light
Ans. 20 The band of seven colours obtained by dispersion of white light is called spectrum.
More Questions for Practice
1. A person can see only objects beyond 1m. From his eyes. Name the defect of the eye.
2. Out of light of blue and red colours which one is scattered most?
3. What is the function of crystalline lens in the human eye?
4. Which phenomenon is responsible for increasing the apparent length of the day by 4 minute?
5. What is the far point of a person suffering from Myopia.
6. What name is given to front transparent part of human eye?
7. Where do we see :(1) Concave and (2) Convex lens in bifocal lenses.
8. What is the nature of image formed by our eye?
9. Name the liquid which is present between eye lens and cornea.
10. Where does most of the refraction of light in an eye occurs?
11. Which kind of lens is an eye lens?
12. What is the cause of dispersion of light?
13. Under very dim light, we are able to see the objects but can not distinguish between colours. why ?
14. What is the range of vision for normal human eye ?
15. How is the amount of light entering the eye controlled ?
16. What is the colour of danger signal? Why?
17. What is rainbow? How is rainbow formed?
18. State two causes of myopic vision.
19. How an uncorrected myopic eye sees far off objects.
20. What is presbyopia? Name the type of lens which can be used to correct presbyopia.
21. Explain why planet do not twinkle at night?
22. Explain about the colour of the sun at sunrise and sunset.
23. Define the term (1) Near point (2) Far point
24. Why is a normal eye not able to see clearly the object closer than 25 cm.
25. Draw a ray diagram to show the refraction of light through a glass prism on
the diagram mark. (a) Incident ray (b) Emergent ray and (c) Angle of deviation
26. How is the dispersed white light recomposed ?
27 The near point of a hypermetropic eye is at 75 cm from the eye. What is the power of the lens required to enable him to read clearly a book held at 25 cm from the eye.


Fifty years ago scientists decided to take a closer look at the stars and the space age was born, an event currently being marked by World Space Week. Since 1957, humans have put monkeys into orbit, men on the moon and launched satellites to explore the planets.
Jobs associated with the final frontier are many and varied - from helping plan missions and designing and building spacecraft, to lecturing the next generation of scientists or studying erupting magnetic structures. Some may even get the chance to make another giant leap for mankind.
Our experts explore the options.
An employer says ...
Fiona Walsh, head of recruitment service and human resources adviser, European Space Agency
We have the Young Graduate Trainee Programme, a one-year scheme whereby we hire approximately 80 recent graduates from all over Europe.
Often our best employees are those who knew at a young age that they wanted to be involved in the space or the aerospace field. This, of course, should not be a deterrent for those who may not have had this yearning.
Our core business is technical, so we tend to hire a large number of scientists and engineers. They could be involved in building and manufacturing satellites and launchers, the exploitation of data coming from the satellites, astronomy or space science.
When our training centre in Cologne makes the calls for astronauts, we get thousands of applications, of which the vast majority don't qualify. A lot of our astronauts are doctors who have an engineering background. Some are pilots: they learn to fly a plane and then try a spacecraft.
To become an astronaut you have to go through very intensive training. There's a tough screening process. And when you're qualified it doesn't mean you will have a flight straight away. The International Space Station is operated between a number of countries and the first European astronaut only went into space last year. Astronauts are in constant training, it can be years before they get their first flight.
A university says ...
Dr Lucie Green, research fellow, Mullard Space Science Laboratory, University College London
Space is an international endeavour so a job in this area means working with scientists and space agencies all around the world. There are all sorts of jobs, such as being a post-doctoral researcher working in international collaborations carrying out research to answer particular science questions. After gaining experience, a post-doc may move on through the university system to a lectureship position - and beyond - where you will be training up the next generation of scientists, as well as doing your own research.
However, to enable the research to take place, software, hardware and a lot of project management is needed, which bring about jobs in these areas.
In fact, the UK provides instrumentation for space research so there are jobs in this country for engineers, both mechanical and electronic, computing experts, project managers, programmers and software engineers.
A PhD is the typical route in, especially for research. However, it isn't the only one. If you want to come into the engineering side, you could follow a vocational training route. You need to work hard and keep focused on the bigger picture. Space science is all about the big questions, such as is there life beyond the Earth? But we need to work together to answer them.
Going into space would truly be the most amazing experience that someone could have. But my ambitions are far more down to Earth. I'm happy looking up.
A graduate recruit says ...
Amanda Regan, engineer, Earth Observation Future Missions, the European Space Research and Technology Centre
I decided I wanted a career in space when I was about 12 years old. I studied for a manufacturing engineering and management degree at Brunel University and an engineering systems Master's at the University of Texas at Austin in the US - I went to Texas on an exchange programme from Brunel. I specialised in space mission design and planning.
After coming back from Texas I worked for nearly two years at a small space systems company in the UK. I wanted to work at ESA but I also wanted to gain more experience, so I applied for one of the one-year trainee placements. I was accepted and worked on an International Space Station external payload project, which will be launched with the Columbus module in a few months.
The interviews at ESA are notoriously tricky - you have to be prepared and think on your feet.
In future missions we work on feasibility and concept studies for earth observation missions. Space mission design is split into four phases - phase A is the concept definition; phase B is the concept development; and phases C to D are when the spacecraft is built. At the end of phase D the spacecraft is launched.
In future missions we focus on the early stages of the process. Typically, the missions we work on will be launched around 2012 to 2015.


(Full story available on the National Geographic website)
Iconic Joshua trees may disappear—but scientists are fighting back
By Philip Kiefer
The desert’s harshness breeds strange bedfellows—desert bats fly hundreds of miles in the night to feed on agave, and seedlings often rely on their dead forebears to provide shelter. But those relationships can make it hard to adapt in a changing climate.
Rising temperatures have set the natural world creeping uphill or northwards in search of relief. But ecosystems don’t move in lock-step. The foxes might outpace the tortoises which might outpace the trees. In the process, the ecological deck is shuffled. These changes threaten to unravel the interspecies networks on which desert organisms depend. And the Joshua tree, an international symbol of the American desert, seems to have been dealt a bad hand.
(Full story here)


Dentoalveolar surgeries are the procedures most often performed by oral and maxillofacial surgeons. These are a group of procedures that involve adding, reshaping or removing hard and soft tissues supporting teeth.
Types of dentoalveolar surgeries include:
- Extraction of a tooth (such as removal of wisdom teeth)
- Complicated tooth extractions (such as impacted teeth)
- Removal of noncancerous lesions, tumor or cysts
- Recontouring or enhancement of the alveolar bone to support placement of a dental implant
- Preparing gum and bone for implant, crown or denture placement
- Exposure of teeth for orthodontics
An OMS may perform dentoalveolar surgery to manage:
- Odontogenic infections (infections that originate in or around the tooth)
- Periradicular pathologies (pathologies around the root of the tooth)
- Erupted, unerupted or impacted teeth
- Third molars (wisdom teeth)
Although extracting one or more teeth is the most common dentoalveolar surgery, any surgery that manages or treats the conditions listed above is known as a dentoalveolar procedure. Dentoalveolar surgery may be performed to eliminate acute or chronic infection, limit or eliminate pain, restore anatomical form or chewing ability, aid in other restorative procedures or remove an existing pathology.
Preparing for Dentoalveolar Surgery
Patients should follow their OMS’s instructions to prepare for dentoalveolar surgery. In most cases, patients should:
- Bring a list of all medications.
- Ensure they have soft foods to eat during recovery.
- Make arrangements for care with family or friends.
- Prepare a recovery bed, couch or recliner.
- Select comfortable clothes for the day of the surgery.
- Follow the OMS’s instructions about eating or drinking before the procedure.
- Discuss any potential questions or worries with the OMS.


Painting in the browser can be costly, but we tend to forget that the browser isn't the only place where it can occur. By testing the limits of the browser capabilities, we sometimes ignore the fact that OS resource usage and machine configurations also affect browser rendering. That these remain outside our control doesn't mean that we should neglect them during development. Otherwise we may reach the limits of the possible sooner than we thought, which will lead to a browser crash.
The browser exists thanks to the operating system, which can affect its painting and even terminate it. If we assume for a second that we have a transparent browser window, then everything underneath will need to be rendered too in order to be visible. In this case, painting the browser and the underlying windows, including the desktop, is a task that may require time sharing of the available machine resources due to the competitive environment in which the rendering occurs. When we resize the browser window and make it smaller, the painting costs inside of it will decrease due to the smaller painting area and the fact that fewer pixels will need to be updated during page loading, scrolling and general user interactions with the page. But the painting area outside the browser increases and because the nature of the resize event is to fire continuously, the cost of the desktop repaint will be introduced to the system, multiple times per second. If we have a huge background photo with lots of icons and text labels that have to be anti-aliased, these costs may slow down the system and thus affect the rate with which we can continue to resize the window.
Every time we minimize or maximize the browser window, we reveal or hide the desktop. The browser window and its content have to shrink/grow and the visible desktop area has to grow/shrink. Animating this process will invoke repaints for every step of the transition between the minimized and maximized states. If we disable these animations, we'll have to repaint only once for each of these two states, which can eliminate lots of calculations. The user may think that the browser responds slowly to interactions and direct manipulation, whereas the possible cause for the bad experience—an overloaded desktop—seems to be standing still.
By preserving window contents while dragging, we make desktop repaints even more obvious. If we are moving the window fast, we can see for a millisecond how the surrounding area (on the desktop) is wiped out until it starts to gradually reappear, following the direction of the movement. In some instances, we can literally "clean" our desktop to the extent we can't see anything on it. To force it to repaint, we can toggle "show desktop" again. But this shows that painting in the browser doesn't occur in isolation.
What we can do to ensure minimal painting costs is to clean our desktop and replace any heavy background images with a single, solid color. Keeping most of our data files on a separate partition and not in subfolders on our desktop allows us to minimize the burden on the OS. When we need these files, we can explore them trough a single window that we keep minimized. Hiding files isn't as hard as it seems—some of them we need rarely, others can be deleted, system icons can also be hidden. Program icons also don't have to be spread on the desktop just to be made directly accessible. We can put all shortcuts in a single folder labeled "Programs" and install a program like Launchy, where we specify the location of this folder. After the file index is created, we can start programs by showing Launchy with <Alt>+<Space> and typing their name. Programs are almost immediately recognized and we can simply press <Enter> to start them. This effectively hides Launchy, but the options allow us to do the same when it loses focus, which is convenient.
We can use the desktop as a file distributor in our system. As soon as new files arrive, we can decide what to do with them. We can use them, transfer them to the appropriate directory if they have long-term value or delete them when they are no longer needed. This eliminates the case where we have many files in a directory that we see rarely and fear to clean up, because we have lost track what was valuable after it was used, but not deleted. On the desktop, new files are always in front of us, directly contributing to visual disorder, which stops our willingness to download more. To keep the space clean, we have no other option except of acting on these files immediately.
By cleaning up the desktop, we eliminate distractions during our work, minimize painting costs for window operations that also affect the browser and finally, we eliminate the possibility that excessive number of files will slow down our system over time.


Directions: Draw three rectangles with a perimeter of 20 units.
How can we tell whether a rectangle has a perimeter of 20 units? How can we adjust our rectangle if it doesn’t have a perimeter of 20 units?
There are an infinite number of answers as long as the side lengths add up to 20 units.
Source: Dan Meyer


Study shows that a single gene mutation may lead to development of type 1 diabetes and other autoimmune diseases.
The research began when Marc Donath, M.D., endocrinologist and researcher at the University Hospital Basel in Switzerland, discovered an interesting pattern of autoimmune disease within the family of one of his patients, a 26-year-old male who had recently been diagnosed with T1D.
The patient showed an uncommonly strong family history of T1D; his sister, father, and paternal cousin had also been diagnosed earlier in their lives. Additionally, another family member had developed ulcerative colitis, also an autoimmune disease.
"This pattern of inheritance was indicative of dominant genetic mutation, and we therefore decided to attempt to identify it," Dr. Donath said.
Four years of analysis using three different genotyping and sequencing techniques pointed to a mutation on the SIRT1 gene as the common indicator of autoimmune disease within the family.
The SIRT1 gene plays a role in regulating metabolism and protecting against age-related disease. To gain more understanding of how this genetic change in SIRT1 leads to T1D, Dr. Donath and his team performed additional studies with animal models of T1D.
When the mutant SIRT1 gene found in the families was expressed in beta cells, those beta cells generated more mediators that were destructive to them. Furthermore, knocking out the normal SIRT1 gene in mice resulted in their becoming more susceptible to diabetes with greatly increased islet destruction.
Dr. Donath speculates that the beta cell impairment and death due to the SIRT1 mutation subsequently activates the immune system toward T1D.
"The identification of a gene leading to type 1 diabetes could allow us to understand the mechanism responsible for the disease and may open up new treatment options," Dr. Donath explained.
The study was recently published in Cell Metabolism.


Julie Straw and team in their book The Work of Leaders discussed three steps of leadership – Crafting a Vision, Building Alignment and Championing Execution. In this article, we discuss the importance of not just crafting a shared vision but also the role of a leader in crafting a shared vision.
To begin with, people like their leaders to have two distinct characteristics – being forward-looking and futuristic and being credible or trustworthy. To get extraordinary things, people must work in the present and focus on the future into the whole realm of possibilities. All things are created twice – once in the mind and then in reality. A leader’s job is to continuously envision new products and services and new business ecosystems that can take the organization towards success.
Leaders must focus on creating long term value for the organization and its customers while focussing on the present for delivering results. By focussing on the future, leaders can provide a sense of meaning and purpose to the organization that binds its people together and inspire them to work hard. By continuously seeking clarity of vision and then enlisting others, leaders create a sense of shared vision.
Motivation theories provide a business case for creating a shared vision. As we know, motivation is essentially of two types – extrinsic and intrinsic. Extrinsic motivation stems from the external environment, for getting rewarded or when we must achieve certain goals set by others. External motivation creates compliance and in some cases defiance. Externally controlled people could stop making efforts once rewards disappear.
Extrinsic motivation is difficult to sustain. However, the second type of motivation – intrinsic motivation is about what one wants to achieve internally. Not set or controlled by others, internal motivation is about our own interests, passion and desires. It gives us tenacity to see through rough times and work with tangible rewards. By enlisting people in the process of shared vision, leaders play on intrinsic motivation of people. By offering a shared vision that everyone feels intrinsically inspired by, leaders create a rich environment where employee engagement and performance are enhanced. The role of a leader in creating a shared vision is in enticing the intrinsic motivating of the people and in building consensus.
Role of a Leader in Crafting a Shared Vision
One of the first steps in crafting a vision is to do some self-reflection and articulate as much as possible one’s likes, passions, interests and inspirations. Because the process of envisioning is more art than science, more emotional than a sequence of activities, it is important to start by articulating what drives and inspires the leader. The role of a leader is in not just self-reflecting but also encouraging the leadership team in an exercise of self-reflection.
Second, by engaging with the larger team, where everyone shares in their values, inspirations, perspectives, questions, hopes and dreams, you could arrive at certain themes or directions that define the overall shared vision. Role of a leader is in engaging the leadership team in a structured process of deriving these idea directions.
Past provides a great way to start looking into the future. It is filled with experiences, data, perspectives, reality and most importantly learning. It gives a picture of what is possible and how long does it take for you as a company to do something new. It provides a good view of what can go wrong as well. While the past does not always portray the future possibilities of an organization, it provides a good way to extrapolate the success and assess what an organization may achieve. The role of a leader is in engaging the leadership team in a systematic process of sharing the highs and lows about the past and arriving at the key learnings form the past.
By assessing the current business ecosystem, leaders can enable the creation of a shared vision. Recent research and surveys involve understanding how the organization creates value for its customers, what the current capability and shortcomings are and how people feel working in the organization. The juice of assessing, reflecting and articulating the current state of the organization is in knowing what must change and what must be preserved in the future.
Imagining the future
The final step of creating a shared vision, which the leader must drive is in imagining a bold future. A future that considers the unfolding market situation, trends and patterns in the buying behavior of the customers, technological advancements and disruptive trends. The role of a leader is in providing a psychologically safe environment for the team to share their version of the vision without the fear of loosing credibility.


"A Kidnapped Santa Claus" is a short story written by L. Frank Baum and published in The Delineator in December 1904. It is a continuation of the story set forth in The Life and Adventures of Santa Claus, telling how Santa Claus was kidnapped by the Daemons in a plan to make children unhappy.
The story was illustrated by Frederick Richardson, who also illustrated Baum's Queen Zixi of Ix a year later. It has been called "one of Baum's most beautiful stories," and constitutes a notable contribution to the mythology of Christmas.
"A Kidnapped Santa Claus" was published two years after Baum's novel on Santa Claus, and shares its mythological cosmos. In the story as in the novel, Santa lives in the Laughing Valley on the border of the Forest of Burzee, and is assisted by Knooks, Ryls, Fairies, and Pixies. In modern editions the two works, novel and short story, are sometimes published together.
Though the short story has strong similarities with the novel, it has been interpreted as presenting "a less rosy view" of the world, in that it shows elements of evil as fundamental to existence, and ineradicable.
The story opens with a quick overview of Santa's castle in the Laughing Valley. Its focus soon switches to the five Caves of the Daemons in nearby (though unnamed) mountains. The Daemons of Selfishness, Envy, Hatred, and Malice resent Santa because children under the influence of his gifts rarely visit their caves. They want to frustrate his efforts and counter his influence. (The Daemon of Repentance goes along with their plan, since children cannot reach his remote cavern without passing through the prior caves of his compatriots.) The Daemons first try to tempt Santa to their own vices; they visit him one by one, and attempt to lure him into selfishness, envy, and hatred. Santa merely laughs at their clumsy efforts. Failing at temptation, the Daemons kidnap Santa instead, lassoing him as he rides in his sleigh on Christmas Eve and binding him in their caverns.
Santa Claus is accompanied on his rounds by a fairy, pixie, knook, and ryl, who travel under the seat of his sleigh. Once the four realize that Santa is gone, they endeavor to complete his mission and deliver the gifts. They generally succeed, though with some mistakes: they send a toy drum to a little girl and a sewing kit to a little boy. Overall, though, they manage to save Christmas.
Then they report Santa's absence; the fairy queen of Burzee understands what has happened. An army of magical creatures is mustered to rescue the missing hero. Meanwhile, though, Santa is released from captivity by the Daemon of Repentance, who has repented the kidnapping. Santa meets the army on its way, and turns it back from attacking the daemons.
In the seventh chapter of The Life and Adventures of Santa Claus, titled "The Great Battle Between Good and Evil," Baum depicts a combat between massed magical forces. Here in the story he chooses a pacifistic alternative to grand conflict, an approach he would also take a few years later in The Emerald City of Oz
The Daemons of the story as pagan figures rather than Christian demons, in that they are not servants of Satan or necessaily evil. Four of the five, the Daemons of Sefishness, Envy, Hatred, and Malice, certainly are bad, but the fifth, the Daemon of Repentance, is a more ambiguous entity.
The obvious model for the Daemon's temptation of Santa is the Temptation of Christ in the Synoptic Gospels (an interesting mix of Christian and pagan elements in one story).
Later editions, adaptations, influences
"A Kidnapped Santa Claus" appeared in an anthology of Christmas stories in 1915. The Baum Bugle reprinted it at Christmas 1968. The story was released in book form in 1969, with a Foreword by Martin Williams and new illustrations by Richard Rosenblum. It has been issued in multiple editions, in multiple forms, since.
In 1989 the story was adapted into a musical play for children, Santa Claus is Missing!, by Sylvia Ashby, with songs by Scott Taylor. Another adaptation came in the form of the animated film Who Stole Santa? in the Oz Kids series (1996). A modernized graphic novel adaptation by artist Alex Robinson was released in 2009. More generally, the idea of kidnapping Santa Claus has been used by other artists in other works, as in Jean Van Leeuwen's book The Great Christmas Kidnapping Caper (1975), Tim Burton's film The Nightmare Before Christmas (1993), and Ruth Ann Pattee's play Can Mrs. Claus Save Christmas? (2000).
- ↑ Michael O. Riley, Oz and Beyond: The Fantasy World of L. Frank Baum, Lawrence, KS, University Press of Kansas, 1997; p. 112.
- ↑ L. Frank Baum, The Complete Life and Adventures of Santa Claus, Holicong, PA, Wildside Press, 2002.
- ↑ L. Frank Baum, L. Frank Baum's Book of Santa Claus, Radford, VA, Wilder Publications, 2007.
- ↑ Katharine M. Rogers, L. Frank Baum, Creator of Oz: A Biography, New York, St. Martin's Press, 2002; p. 102.


Bells creek vegetation and fauna management was conducted in approximately 23 hectares of a predominant regrowth area, consisting of a dominant Slash Pine floristic composition. Few Eucalypts were on site. However, as the Eucalypt species was Scribbly Gum, hollow bearing structures were present. Utilising D6 and D8 Bulldozers and Excavators it was essential to clear the site effectively, professionally and efficiently to maximise fauna survivorship and reduce fauna habitat impact.
Habitat variance and potential fauna protective cover was limited as a direct result of very high Slash Pine density and the correlating lack of suitable ground cover and fauna habitat assets. Several Northern Brown Bandicoots were afforded safe egress paths into adjacent delineated green zones. The capture of a 2.5 meter Coastal Carpet Python on site was relocated into the nearby Nature Reserve.
Coordinating fauna management on a large site requires a high level of skill sets. Knowledge of the immediate habitat variation and the potential fauna that could be present was essential in constructing a fauna spotter service implementation plan.
Snake capture challenges are often involved with snake encounters on site. This is a key reason why experienced and professional fauna spotters are required in order to minimise harm to the snake during capture whilst maximising human safety. .


As we all know, human is considered to be the best creature in the world. It is said so because human has mind and also senses so that we can think and distinguish which one is right or wrong. Human are also completed with creativity which enables us to create such a wonderful invention or action just in order to survive in this world. It is unlike with animals, plants, nature and any other creation of God, humans is the only creature which can make this world to be better or even worse. The most sophisticated invention is what is called with technology.
Although human is assumed to be the best creature in the world, human also have their own weaknesses. That is the reason why technology is made. It is created to help humans to be easier in doing their activity. The most interesting one is the invention of robot. Mostly, the purpose of making robot is to help human to do their activity which can harm their life. For example is robot which is made to fly to the moon or robot which is made to dive across the deep sea. Therefore, the impossible activities which are seem to be so difficult to do become easy by the help of robot.
Besides, there is also a robot which is made with the purpose to give amusement to human. One of the examples is the robot which can dance and sing. Overall, the invention of this technology is so beneficial for helping human. Robot is called as the artificial innovation of human being then.


There’s a certain four letter word that strikes great fear into the hearts of many people: math. It has a reputation for being a subject of the elite — a terrible, confusing, jumbled mess of illogical expressions and rules that many people just give up trying to decipher at some point. Nevertheless, many students of mathematics (formal and informal) persevere through years of algebra and arithmetic to find themselves facing a very different beast: calculus.
In truth, mathematics is complicated and advanced, and it took hundreds of years to develop this language that can accurately describe the universe in which we live.
Initially, math arose to solve problems and predict outcomes in everyday life, and as humans became more interested in how the world worked, they were faced with the limitations of their current mathematical theories. That’s why many people throughout history worked to create new and better models of nature, leading to advanced mathematics. It’s also the reason Sir Isaac Newton and other innovators were prompted to create some of the most dreaded mathematical equations that we know today.
To understand the need Newton felt for more precise mathematics, you first need a brief understanding of what math existed before he came along and changed everything.
In ancient times (around 580–212 BCE), three notable philosophers — Pythagoras, Euclid, and Archimedes — created what we know now as algebra and geometry, but they struggled to unify them. Up until this point, algebra was done without the ideal tools, such as the plus, minus, and multiplication/division symbols or a numbering system that was easy to work with (imagine doing algebra with Roman numerals).
In the late 1500s, Rene Descartes unified algebra, which was used as an analytical tool, along with the geometric shapes. He found that a point on a plane can be described using two numbers, and from that information, equations of geometric figures were born.
Both men did quite a lot of work forming a language of numbers that could accurately describe nature. It is worth noting that Newton developed calculus eight years before Leibniz, but Leibniz is known for developing modern European mathematics because he introduced carefully drawn symbols and rules — many people say he was responsible for creating the equals sign (=). Both men claimed that the other plagiarized them for the rest of their lives, a conflict known as the “great sulk.”
So why was this new and complicated form of mathematics invented and how does one manage to come up with such an abstract idea?
Newton was foremost a physicist, and in his day, he tackled many difficult issues in physics, the most famous of which was gravity. Newton is known for developing the laws of motion and gravitation, which undoubtedly led to his work in calculus. When trying to describe how an object falls, Newton found that the speed of the object increased every split second and that no mathematics currently used could describe the object at any moment in time.
Another tale of Newton’s reasoning is that a colleague of his asked why the orbits of the planets were in an ellipse. Newton took some time to ponder the question and came back with the fact that the ellipses are actually sections of cones. Armed with calculus, he could describe exactly how those sections behaved.
These types of questions and the fact that Cambridge University, where Newton studied, was closed due to numerous outbreaks of the plague, drove Newton to expand on mathematics and develop the concepts of differential and integral calculus.
The answer to the question of how to actually invent a new form of mathematics is deceptively simple: Newton forced relationships between physical phenomena and the mathematics of the day. Through trial and error (and quite a bit of ingenuity), Newton saw the need for a whole new math, and this came from his conceptual understanding of physics. More simply, Newton already knew the concepts of calculus because he was describing gravity and planets. It was a matter of writing it down and showing proof that it works.
Nobody would claim that Newton wasn’t a brilliant man, but calculus has been refined for over 300 years with many features added (like limits, which make everything easier), meaning that no longer does one have to be a genius to understand it. Today, a student who has a concept of algebra already knows more than Newton did when he invented calculus. Math students of the present day should not fear calculus. It isn’t a math just for the elite or for the genius; it’s for anyone who has the time and discipline to learn it.