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L_0728 | newtons second law | T_3604 | FIGURE 14.7 This empty trunk has a mass of 10 kilo- grams. The weights also have a mass of 10 kilograms. If the weights are placed in the trunk, what will be its mass? How will this affect its acceleration? | image | textbook_images/newtons_second_law_22286.png |
L_0729 | newtons third law | T_3606 | FIGURE 14.9 Each example shown here includes an action and reaction. | image | textbook_images/newtons_third_law_22288.png |
L_0729 | newtons third law | T_3607 | FIGURE 14.10 A bowling ball and a softball differ in mass. How does this affect their momen- tum? | image | textbook_images/newtons_third_law_22289.png |
L_0729 | newtons third law | T_3609 | FIGURE 14.11 How can you tell momentum has been conserved in this collision? | image | textbook_images/newtons_third_law_22290.png |
L_0731 | buoyancy of fluids | T_3624 | FIGURE 15.12 Fluid pressure exerts force on all sides of this object, but the force is greater at the bottom of the object where the fluid is deeper. | image | textbook_images/buoyancy_of_fluids_22302.png |
L_0731 | buoyancy of fluids | T_3626 | FIGURE 15.13 Whether an object sinks or floats depends on its weight and the strength of the buoyant force acting on it. | image | textbook_images/buoyancy_of_fluids_22303.png |
L_0731 | buoyancy of fluids | T_3627 | FIGURE 15.14 The substances pictured here float in a fluid because they are less dense than the fluid. | image | textbook_images/buoyancy_of_fluids_22304.png |
L_0732 | work | T_3628 | FIGURE 16.2 Carrying a box while walking does not result in work being done. Work is done only when the box is first lifted up from the ground. Can you explain why? | image | textbook_images/work_22307.png |
L_0732 | work | T_3630 | FIGURE 16.3 Weight lifters do more work when they move weights a longer distance or move heavier weights. | image | textbook_images/work_22308.png |
L_0732 | work | T_3632 | FIGURE 16.4 Which way of removing leaves would take less effort on your part? | image | textbook_images/work_22309.png |
L_0732 | work | T_3632 | FIGURE 16.5 Hair dryers vary in power. How do you think this affects drying time? | image | textbook_images/work_22310.png |
L_0732 | work | T_3634 | FIGURE 16.6 The horses and the tractor are both pulling a plow. The horses provide less horsepower than the tractor. Which do you think will get the job done faster? | image | textbook_images/work_22311.png |
L_0733 | machines | T_3636 | FIGURE 16.8 Both of these machines increase the force applied by the user, while reducing the distance over which the force is applied. | image | textbook_images/machines_22313.png |
L_0733 | machines | T_3637 | FIGURE 16.9 Both of these machines increase the dis- tance over which force applied, while re- ducing the strength of the force. | image | textbook_images/machines_22314.png |
L_0733 | machines | T_3638 | FIGURE 16.10 Both of these machines change the direction over which force is applied. The claw hammer also increases the strength of the force. | image | textbook_images/machines_22315.png |
L_0733 | machines | T_3642 | FIGURE 16.11 A ramp is a machine because it makes work easier by changing a force. How does it change force? | image | textbook_images/machines_22316.png |
L_0733 | machines | T_3644 | FIGURE 16.12 The input force is applied along the length of the sloping ramp surface. The output force is applied along the height of the ramp. The input distance is greater than the output distance. This means that the input force is less than the output force. | image | textbook_images/machines_22317.png |
L_0734 | simple machines | T_3646 | FIGURE 16.14 An inclined plane makes it easier to move objects to a higher elevation. | image | textbook_images/simple_machines_22319.png |
L_0734 | simple machines | T_3648 | FIGURE 16.15 The thin edge of a knife or chisel enters an object and forces it apart. | image | textbook_images/simple_machines_22320.png |
L_0734 | simple machines | T_3649 | FIGURE 16.16 All of these examples are screws. Can you identify the inclined plane in each example? | image | textbook_images/simple_machines_22321.png |
L_0734 | simple machines | T_3649 | FIGURE 16.17 The threads of a screw or bolt may be closer together or farther apart. How does this affect its ideal mechanical ad- vantage? | image | textbook_images/simple_machines_22322.png |
L_0734 | simple machines | T_3650 | FIGURE 16.18 Using a hammer to remove a nail changes both the direction and strength of the applied force. Where is the fulcrum of the hammer when it is used in this way? | image | textbook_images/simple_machines_22323.png |
L_0734 | simple machines | T_3651 | FIGURE 16.19 Which class of lever would you use to carry a heavy load, sweep a floor, or pry open a can of paint? | image | textbook_images/simple_machines_22324.png |
L_0734 | simple machines | T_3653 | FIGURE 16.20 Both a Ferris wheel and a car steering wheel have an outer wheel and an inner axle. | image | textbook_images/simple_machines_22325.png |
L_0734 | simple machines | T_3654 | FIGURE 16.21 In both of these examples, pulling the rope turns the wheel of the pulley. | image | textbook_images/simple_machines_22326.png |
L_0734 | simple machines | DD_0211 | Shown in the diagram are the six types of simple machines. A simple machine is a mechanical device that makes work easier. It includes the inclined plane, wedge, lever, wheel and axle, screw and pulley. An inclined plane is a flat surface that is slanted, or inclined, so it can help move objects across distances. A common inclined plane is a ramp used to lift heavy objects in a back of a truck. Instead of using the smooth side of the inclined plane to make work easier, you can also use the pointed edges to do other kinds of work. When you use the edge to push things apart, this movable inclined plane is called a wedge. An ax blade is one example of a wedge. Any tool that pries something loose is a lever. Levers can also lift objects. A lever is an arm that turns against a fulcrum (the point or support on which a lever pivots). Think of the claw end of a hammer that you use to pry nails loose; itÕs a lever. The Wheel and Axle makes work easier by moving objects across distances. The wheel (or round end) turns with the axle (or cylindrical post) causing movement. On a wagon, for example, a container rests on top of the axle to help transport heavy objects. A Screw helps you do work is that it can be easily turned to move itself through a solid space like turning a jar cover to keep it the jar air tight. Instead of an axle, a wheel could also rotate a rope, cord, or belt. This variation of the wheel and axle is the pulley. In a pulley, a cord wraps around a wheel. Instead of an axle, you can use the wheelÕs rotation to raise and lower objects, making work easier. On a flagpole, for example, a rope is attached to a pulley to raise and lower the flag more easily. | image | teaching_images/simple_machines_9246.png |
L_0735 | compound machines | T_3656 | FIGURE 16.24 A pair of scissors is a compound machine consisting of levers and wedges. | image | textbook_images/compound_machines_22329.png |
L_0735 | compound machines | T_3658 | FIGURE 16.25 As a third-class lever, how does a fishing rod change the force applied to the rod? How does the reel help land the fish? | image | textbook_images/compound_machines_22330.png |
L_0736 | types of energy | T_3660 | FIGURE 17.2 It takes energy to swing a bat. Where does the batter get her energy? | image | textbook_images/types_of_energy_22332.png |
L_0736 | types of energy | T_3661 | FIGURE 17.3 All of these photos show things that have kinetic energy because they are moving. | image | textbook_images/types_of_energy_22333.png |
L_0736 | types of energy | T_3662 | FIGURE 17.4 Before leaves fall from trees in autumn, they have potential energy. Why do they have the potential to fall? | image | textbook_images/types_of_energy_22334.png |
L_0736 | types of energy | T_3663 | FIGURE 17.5 All three of these people have gravita- tional potential energy. Can you think of other examples? You Try It! Problem: Kris is holding a 2-kg book 1.5 m above the floor. What is the gravitational potential energy of the book? | image | textbook_images/types_of_energy_22335.png |
L_0736 | types of energy | T_3664 | FIGURE 17.6 Changing the shape of an elastic material gives it potential energy. | image | textbook_images/types_of_energy_22336.png |
L_0736 | types of energy | T_3667 | FIGURE 17.7 Energy continuously changes back and forth between potential and kinetic energy on a swing or trampoline. | image | textbook_images/types_of_energy_22337.png |
L_0737 | forms of energy | T_3670 | FIGURE 17.9 Kinetic and potential energy add up to mechanical energy. | image | textbook_images/forms_of_energy_22339.png |
L_0737 | forms of energy | T_3671 | FIGURE 17.10 Chemical energy is stored in wood and released when the wood burns. | image | textbook_images/forms_of_energy_22340.png |
L_0737 | forms of energy | T_3672 | FIGURE 17.11 A lightning bolt is a powerful discharge of electrical energy. A battery contains stored chemical energy and converts it to electrical energy. | image | textbook_images/forms_of_energy_22341.png |
L_0737 | forms of energy | T_3674 | FIGURE 17.12 In the sun, hydrogen nuclei fuse to form helium nuclei. This releases a huge amount of energy, some of which reaches Earth. | image | textbook_images/forms_of_energy_22342.png |
L_0737 | forms of energy | T_3674 | FIGURE 17.13 Atoms are moving at the same speed in the soup on the spoon as they are in the soup in the pot. However, there are more atoms of soup in the pot, so it has more thermal energy. | image | textbook_images/forms_of_energy_22343.png |
L_0737 | forms of energy | T_3675 | FIGURE 17.14 Radio waves, microwaves, and X rays are examples of electromagnetic energy. | image | textbook_images/forms_of_energy_22344.png |
L_0737 | forms of energy | T_3676 | FIGURE 17.15 Vibrating objects such as drumheads pro- duce sound energy. | image | textbook_images/forms_of_energy_22345.png |
L_0737 | forms of energy | T_3677 | FIGURE 17.16 Energy is constantly changing form. Can you think of other examples of energy conversions? | image | textbook_images/forms_of_energy_22346.png |
L_0738 | energy resources | T_3678 | FIGURE 17.18 Whitewater rafting is an exciting sport. | image | textbook_images/energy_resources_22348.png |
L_0738 | energy resources | T_3679 | FIGURE 17.19 Do you use any of these fossil fuels? How do you use them? sunlight to stored chemical energy in food, which was eaten by other organisms. After the plants and other organisms died, their remains gradually changed to fossil fuels as they were pressed beneath layers of sediments. Petroleum and natural gas formed from marine organisms and are often found together. Coal formed from giant tree ferns and other swamp plants. When fossil fuels burn, they release thermal energy, water vapor, and carbon dioxide. Carbon dioxide produced by fossil fuel use is a major cause of global warming. The burning of fossil fuels also releases many pollutants into the air. Pollutants such as sulfur dioxide form acid rain, which kills living things and damages metals, stonework, and other materials. Pollutants such as nitrogen oxides cause smog, which is harmful to human health. Tiny particles, or particulates, released when fossil fuels burn also harm human health. Natural gas releases the least pollution; coal releases the most (see Figure 17.20). Petroleum has the additional risk of oil spills, which may seriously damage ecosystems. | image | textbook_images/energy_resources_22349.png |
L_0738 | energy resources | T_3679 | FIGURE 17.20 This table compares the levels of several air pollutants released by the burning of natural gas, oil, and coal. | image | textbook_images/energy_resources_22350.png |
L_0738 | energy resources | T_3680 | FIGURE 17.21 Do you remember Japans 2011 nuclear disaster? (Note: the map on the right is not to scale.) | image | textbook_images/energy_resources_22351.png |
L_0738 | energy resources | T_3688 | FIGURE 17.22 Which of the energy resources in this circle graph are renewable? | image | textbook_images/energy_resources_22352.png |
L_0738 | energy resources | T_3688 | FIGURE 17.23 The U.S. uses far more oil than any other country in the world. It is even far ahead of the next largest oil user, which is China. The differences in use per person in these countries are even greater. | image | textbook_images/energy_resources_22353.png |
L_0738 | energy resources | T_3688 | FIGURE 17.24 Small savings in energy really add up when everybody conserves energy. | image | textbook_images/energy_resources_22354.png |
L_0739 | temperature and heat | T_3692 | FIGURE 18.1 The cocoa is scalding hot. The bath water is comfortably warm. Why does the bath water have more thermal energy than the cocoa? | image | textbook_images/temperature_and_heat_22355.png |
L_0739 | temperature and heat | T_3694 | FIGURE 18.2 The red liquid in this thermometer is alcohol. Alcohol expands uniformly over a wide range of temperatures. This makes it ideal for use in thermometers. | image | textbook_images/temperature_and_heat_22356.png |
L_0739 | temperature and heat | T_3695 | FIGURE 18.3 A cool spoon gets warmer when it is placed in a hot liquid. Can you explain why? | image | textbook_images/temperature_and_heat_22357.png |
L_0739 | temperature and heat | T_3696 | FIGURE 18.4 Sand on a beach heats up quickly in the sun because sand has a relatively low specific heat. | image | textbook_images/temperature_and_heat_22358.png |
L_0740 | transfer of thermal energy | T_3698 | FIGURE 18.6 How is thermal energy transferred in each of these examples? | image | textbook_images/transfer_of_thermal_energy_22360.png |
L_0740 | transfer of thermal energy | T_3701 | FIGURE 18.7 Thermal insulators have many practical uses. Can you think of others? | image | textbook_images/transfer_of_thermal_energy_22361.png |
L_0740 | transfer of thermal energy | T_3702 | FIGURE 18.8 Convection currents carry thermal energy throughout the soup in the pot. | image | textbook_images/transfer_of_thermal_energy_22362.png |
L_0740 | transfer of thermal energy | T_3702 | FIGURE 18.9 A sea breeze blows toward land during the day, and a land breeze blows toward water at night. Why does the wind change direction after the sun goes down? | image | textbook_images/transfer_of_thermal_energy_22363.png |
L_0740 | transfer of thermal energy | T_3703 | FIGURE 18.10 Earth is warmed by energy that radiates from the sun. Earth radiates some of the energy back into space. Green- house gases (GHGs) trap much of the re- radiated energy, causing an increase in the temperature of the atmosphere close to the surface. | image | textbook_images/transfer_of_thermal_energy_22364.png |
L_0740 | transfer of thermal energy | DD_0212 | This diagram shows convection currents. Convection is the transfer of heat from one place to another by the movement of fluids. The heat source lies at the bottom of the diagram. The heat generated by this source causes the air next to it, to warm up. Warm air is lighter than cool air, and hence it rises up. As it rises up, it moves away from the heat source and cools down. As it cools down, it gets heavier and sinks towards the heat source. This cycle continues and causes a convection current. | image | teaching_images/convection_of_air_8050.png |
L_0740 | transfer of thermal energy | DD_0213 | This diagram shows the phenomena of the transfer of thermal energy. It happens by the convection of hot and cold air. The sun heats up the air, making it warm and less dense. Less dense air tends to go up, cooling down as doing it. Cool air becomes more dense and tends to sink, and wind does the job of making the air travel through different places, warming or cooling as he goes. | image | teaching_images/convection_of_air_6657.png |
L_0741 | using thermal energy | T_3705 | FIGURE 18.12 When water is heated in the boiler, it expands. It might burst the pipes of the system if it werent for the expansion tank. This tank holds excess water after it ex- pands. | image | textbook_images/using_thermal_energy_22366.png |
L_0741 | using thermal energy | T_3706 | FIGURE 18.13 The warm-air vent is placed near the floor of the room. Warm air is less dense than cold air so it rises. If the warm-air vent were placed near the ceiling instead, how would this affect the transfer of thermal energy throughout the room? | image | textbook_images/using_thermal_energy_22367.png |
L_0741 | using thermal energy | T_3708 | FIGURE 18.14 A refrigerator must do work to reverse the normal direction of heat flow. | image | textbook_images/using_thermal_energy_22368.png |
L_0741 | using thermal energy | T_3710 | FIGURE 18.15 Thermal energy is converted to the kinetic energy of the moving piston inside the cylinder. The moving piston, in turn, can be used to turn a turbine or do other useful work. | image | textbook_images/using_thermal_energy_22369.png |
L_0742 | characteristics of waves | T_3712 | FIGURE 19.1 A drop of water causes a disturbance that travels through the pond as a wave. | image | textbook_images/characteristics_of_waves_22371.png |
L_0742 | characteristics of waves | T_3716 | FIGURE 19.2 In a transverse wave, the medium moves at right angles to the direction of the wave. | image | textbook_images/characteristics_of_waves_22372.png |
L_0742 | characteristics of waves | T_3716 | FIGURE 19.3 Crests and troughs are the high and low points of a transverse wave. | image | textbook_images/characteristics_of_waves_22373.png |
L_0742 | characteristics of waves | T_3716 | FIGURE 19.4 An S wave is a transverse wave that trav- els through rocks under Earths surface. | image | textbook_images/characteristics_of_waves_22374.png |
L_0742 | characteristics of waves | T_3717 | FIGURE 19.5 In a longitudinal wave, the medium moves back and forth in the same direction as the wave. | image | textbook_images/characteristics_of_waves_22375.png |
L_0742 | characteristics of waves | T_3719 | FIGURE 19.6 The compressions and rarefactions of a longitudinal wave are like the crests and troughs of a transverse wave. | image | textbook_images/characteristics_of_waves_22376.png |
L_0742 | characteristics of waves | T_3719 | FIGURE 19.7 P waves are longitudinal waves that travel through rocks under Earths surface. | image | textbook_images/characteristics_of_waves_22377.png |
L_0742 | characteristics of waves | T_3720 | FIGURE 19.8 Surface waves are both transverse and longitudinal waves. | image | textbook_images/characteristics_of_waves_22378.png |
L_0743 | measuring waves | T_3721 | FIGURE 19.11 Wave amplitude and wavelength are two important measures of wave size. | image | textbook_images/measuring_waves_22381.png |
L_0743 | measuring waves | T_3723 | FIGURE 19.12 Both of these waves have the same ampli- tude, but they differ in wavelength. Which wave has more energy? | image | textbook_images/measuring_waves_22382.png |
L_0743 | measuring waves | T_3725 | FIGURE 19.13 A transverse wave with a higher fre- quency has crests that are closer to- gether. | image | textbook_images/measuring_waves_22383.png |
L_0743 | measuring waves | DD_0214 | The figure shows a transverse wave. In a transverse wave, wave amplitude is the height of each crest above the resting position. The higher the crests are, the greater the amplitude. Another important measure of wave size is wavelength. Wave amplitude is the maximum distance the particles of a medium move from their resting position when a wave passes through. The resting position (dotted line in the middle of the wave) is where the particles would be in the absence of a wave. Wavelength can be measured as the distance between two adjacent crests of a transverse wave. It is usually measured in meters. Wavelength is related to the energy of a wave. Short-wavelength waves have more energy than long-wavelength waves of the same amplitude. | image | teaching_images/waves_9296.png |
L_0743 | measuring waves | DD_0215 | This diagram represents a sound wave and its characteristics. The peak of a wave is called compression or crest. The valley of a wave is called rarefaction or trough. Wave length is the length between two consecutive peaks, i.e. crest or two consecutive valleys, i.e. trough of a wave. Louder sound has shorter wavelength and softer sound has longer wavelength. Magnitude of maximum disturbance on either side of the normal position or mean value in a medium is called amplitude. In other words, amplitude is the distance from normal to the crest or trough. Time required to produce one complete wave is called time period or time taken to complete on oscillation is called the time period of the sound wave. The number of sound waves produced in unit time is called the frequency of sound waves. Frequency is the reciprocal of the time period of wave. Distance covered by sound wave in unit time is called the velocity of sound wave. | image | teaching_images/waves_7678.png |
L_0744 | wave interactions and interference | T_3730 | FIGURE 19.14 This man is sending sound waves toward a rock wall so he can hear an echo. | image | textbook_images/wave_interactions_and_interference_22384.png |
L_0744 | wave interactions and interference | T_3730 | FIGURE 19.15 Ocean waves are reflected by rocks on shore. | image | textbook_images/wave_interactions_and_interference_22385.png |
L_0744 | wave interactions and interference | T_3731 | FIGURE 19.16 Waves strike a wall at an angle, called the angle of incidence. The waves are re- flected at the same angle, called the angle of reflection, but in a different direction. Both angles are measured relative to a line that is perpendicular to the wall. | image | textbook_images/wave_interactions_and_interference_22386.png |
L_0744 | wave interactions and interference | T_3731 | FIGURE 19.17 This pencil looks broken where it enters the water because of refraction of light waves. | image | textbook_images/wave_interactions_and_interference_22387.png |
L_0744 | wave interactions and interference | T_3732 | FIGURE 19.18 The person can hear the radio around the corner of the building because of the diffraction of sound waves. | image | textbook_images/wave_interactions_and_interference_22388.png |
L_0744 | wave interactions and interference | T_3732 | FIGURE 19.19 An obstacle or opening that is shorter than the wavelength causes greater diffraction of waves. | image | textbook_images/wave_interactions_and_interference_22389.png |
L_0744 | wave interactions and interference | T_3734 | FIGURE 19.20 Constructive interference increases wave amplitude. | image | textbook_images/wave_interactions_and_interference_22390.png |
L_0744 | wave interactions and interference | T_3736 | FIGURE 19.21 Destructive interference decreases wave amplitude. | image | textbook_images/wave_interactions_and_interference_22391.png |
L_0748 | characteristics of sound | T_3770 | FIGURE 20.1 This tree cracked and fell to the ground in a storm. Can you imagine what it sounded like when it came crashing down? | image | textbook_images/characteristics_of_sound_22407.png |
L_0748 | characteristics of sound | T_3771 | FIGURE 20.2 Plucking a guitar string makes it vibrate. The vibrating string sends sound waves through the air in all directions. | image | textbook_images/characteristics_of_sound_22408.png |
L_0748 | characteristics of sound | T_3775 | FIGURE 20.3 High-decibel sounds can damage the ears and cause loss of hearing. Which sounds in the graph are dangerously loud? | image | textbook_images/characteristics_of_sound_22409.png |
L_0748 | characteristics of sound | T_3775 | FIGURE 20.4 The energy of sound waves spreads out over a greater area as the waves travel farther from the sound source. This di- agram represents just a small section of the total area of sound waves spreading out from the source. Sound waves ac- tually travel away from the source in all directions. As distance from the source increases, the area covered by the sound waves increases, lessening their inten- sity. | image | textbook_images/characteristics_of_sound_22410.png |
L_0748 | characteristics of sound | T_3776 | FIGURE 20.5 A piccolo and a tuba sound very differ- ent. One difference is the pitch of their sounds. | image | textbook_images/characteristics_of_sound_22411.png |
L_0748 | characteristics of sound | T_3777 | FIGURE 20.6 The sirens pitch changes as the police car zooms by. Can you explain why? | image | textbook_images/characteristics_of_sound_22412.png |
L_0749 | hearing sound | T_3779 | FIGURE 20.7 The three main parts of the ear have different functions in hearing. | image | textbook_images/hearing_sound_22413.png |
L_0749 | hearing sound | T_3782 | FIGURE 20.8 This highly magnified image of a hair cell shows the tiny hair-like structures on its surface. What function do the "hairs" play in hearing? | image | textbook_images/hearing_sound_22414.png |
L_0749 | hearing sound | T_3782 | FIGURE 20.9 The louder the sounds are, the less time you should be exposed to them for the sake of your hearing. | image | textbook_images/hearing_sound_22415.png |
L_0750 | using sound | T_3786 | FIGURE 20.12 A drum, saxophone, and violin represent the three basic categories of musical in- struments. Can you name other instru- ments in each category? | image | textbook_images/using_sound_22418.png |
L_0750 | using sound | T_3789 | FIGURE 20.13 Bats use ultrasound to find prey. | image | textbook_images/using_sound_22419.png |
L_0750 | using sound | T_3790 | FIGURE 20.14 Sonar works on the same principle as echolocation. | image | textbook_images/using_sound_22420.png |
L_0750 | using sound | T_3791 | FIGURE 20.15 This ultrasound image shows an unborn baby inside its mothers body. Do you see the babys face? | image | textbook_images/using_sound_22421.png |
L_0751 | electromagnetic waves | T_3793 | FIGURE 21.1 Magnetic and electric fields are invisible areas of force surrounding magnets and charged particles. The field lines in the diagrams represent the direction and location of the force. | image | textbook_images/electromagnetic_waves_22422.png |
L_0751 | electromagnetic waves | T_3794 | FIGURE 21.2 An electromagnetic wave starts with a vibrating charged particle. | image | textbook_images/electromagnetic_waves_22423.png |
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