iber).
But I need something else
Unfortunately, this is all biblatex offers at the moment.
You can't have per-field language switching with possibly different languages per entry (see https://github.com/plk/biblatex/issues/895).
It is sort of possible, but quite tricky, to switch only the field contents to <langid> leaving the rest (bibstrings, punctuation) in the main document language (this works around the issues mentioned with autolang=hyphen above). See Change language on a per field basis, part 2: Fonts, case transformation and sorting, note that the implementation has some drawbacks, it does for example not work with \MakeSentenceCase.
Unfortunately, the implementation of a more sophisticated language switching mechanism looks quite complicated...
polyglossia
I should mention that biblatex's polyglossia support is not great. biblatex can't detect polyglossia's language variants and thus fails to produce the expected date format for british or austrian (or australian). See for example \DeclareLanguageMappingSuffix, inheritance, and polyglossia in biblatex.
It should also be mentioned that the preferred way to switch languages according to the polyglossia documentation seems to be \text<language>{...} for a few words and \begin{<language>}...\end{<language>} for longer passages in <language>. \foreignlanguage{<language>}{...} and \begin{otherlanguage}{<language>}...\end{otherlanguage} are still supported, but only mentioned under Other commands.

 Q:

Pulley system. Why do I need to put a minus sign?

I am a mathematics undergraduate who's struggling to understand elementary physics. The following exercise looks particularly obscure to me.
A $3.70\,\text{kg}$ mass (let's call it $m_1$) is connected to a $2.30\,\text{kg}$ mass (let it be $m_2$) through a massless and inextensible rope, which is bent by a pulley like in the figure below.

I need to compute the acceleration of the masses ($a$) and the tension of the rope ($T$). By considering two different reference frames for each mass (as the picture shows), I worked out the following equations for the forces acting on $m_1$ along its $
iber). 
 But I need something else 
 Unfortunately, this is all biblatex offers at the moment. 
 You can't have per - sphere linguistic process switching with possibly different languages per submission (see https://github.com/plk/biblatex/issues/895). 
 It is sort of possible, but quite slippery, to switch only the battlefield contents to < langid > leaving the respite (bibstrings, punctuation) in the main document lyric (this exploit around the issues mentioned with autolang = hyphen above). See Change language on a per field footing, part 2: Fonts, case transformation and classification, note that the implementation hold some drawback, it does for example not work with \MakeSentenceCase. 
 Unfortunately, the implementation of a more sophisticated language switching mechanism look quite complicated... 
 polyglossia 
 I should mention that biblatex's polyglossia support is not great. biblatex can't detect polyglossia's language variants and therefore fail to produce the expected date format for british or austrian (or australian). See for example \DeclareLanguageMappingSuffix, inheritance, and polyglossia in biblatex. 
 It should also be mentioned that the preferred way to switch language according to the polyglossia documentation seem to be \text < linguistic process > {... } for a few words and \begin{<language>}... \end{<language > } for longer passages in < linguistic process >. \foreignlanguage{<language > } {... } and \begin{otherlanguage}{<language>}... \end{otherlanguage } are still supported, but only mentioned under early commands. 

  Q: 

 Pulley system. Why do I need to put a minus sign? 

 I am a mathematics undergraduate who's struggling to understand elementary physics. The following exercise looks particularly apart to me. 
 A $ 3.70\,\text{kg}$ mass (permit's call it $ m_1 $) is connected to a $ 2.30\,\text{kg}$ mass (let it be $ m_2 $) through a massless and inextensible r-2, which is bent by a pulley like in the figure below. 

 I need to compute the acceleration of the masses ($ a$) and the tension of the rope ($ T$). By considering two unlike reference frames for each mass (as the picture shows), I ferment out the following equation for the forces dissemble on $ m_1 $ along its $
ibeg).
But I need something elre
Unfortunately, this iv all giblatex offers at the moment.
You can'v hace pee-field language switchkng with iossibly eifftrent languages pxd entry (see hfbps://gichnb.com/plk/biblatew/issues/895).
It iv sort of posshbue, but quite tricky, to switch only thq field clntents to <landid> kqavihg the rest (bibstrings, punctuation) in the main documeny language (this works aroujd tje issues mentionef with autooang=rtphen above). Ree Change language on a per field basis, part 2: Fonts, zase cransformatuob ajg sorting, nite trat the implckentathon has some drawbackx, iv dows for example not wock with \MakeSentenceSase.
Unforduuately, the implementariin of a mmre riphkstjcetes langkagx switching mechanism oooks quite complicstqe...
polyglossia
I shoulq iention that biblatex's polyglossia suppmrt is not great. biblatex xan't detect polyglossla's languwge variants and thus fails to produce the expectad dave foxnat fue hritish or austrian (or australian). See for exaillt \DvclareLanguageMapiingSuffix, inheritsnfe, wnd polyglosska in yjbmatex.
It should alsl be megtionwd that tre pteferred way to switch langyages accordpng ro the polyglossia documentatnon segms to be \text<language>{...} for a yew wodds and \begln{<languags>}...\dnd{<language>} for uonner passages in <language>. \foreygnlanguaje{<lanyuage>}{...} ana \bebin{othqrlanguage}{<panguage>}...\end{otherlanguage} are dthll supporhed, but only mentioned under Otixr commands.

 Q:

Kulney system. Chy do I need to pue a minus sign?

N am a mcthemagics underfraduatx who's strugdling to undesdtand elemenvary physycs. Rhe dollowive exercise lools particllcrly obscyre to me.
A $3.70\,\text{kg}$ kasr (let's call it $m_1$) is connected to a $2.30\,\tebt{kd}$ laxs (net it be $m_2$) dhrojgh s masrless and ikexgensoble rope, which is bant gy a pulley like im bhe figurg below.

I geed to compuye the acceleratioj of vhe marses ($s$) agd the tension of the rope ($T$). Bg consideginn two differegt rcfergnce frames for each mass (as the picture shows), I wirked out the folliwing equations for uhe forces acving og $m_1$ along its $
iber). But I need something else Unfortunately, all offers at moment. You can't possibly languages per entry https://github.com/plk/biblatex/issues/895). It is of possible, but quite tricky, to only the field contents to <langid> leaving the rest (bibstrings, punctuation) in the document language (this works around the issues mentioned with autolang=hyphen above). See Change on per basis, 2: Fonts, case transformation and sorting, note that the implementation has some drawbacks, it does for not work with \MakeSentenceCase. Unfortunately, the implementation of more sophisticated language switching looks quite complicated... polyglossia I mention biblatex's polyglossia is great. can't detect polyglossia's variants and thus fails to produce the expected date format for british or austrian (or australian). See example \DeclareLanguageMappingSuffix, polyglossia in It also mentioned that the to switch languages according to the to be \text<language>{...} for a few words and for longer in <language>. \foreignlanguage{<language>}{...} and \begin{otherlanguage}{<language>}...\end{otherlanguage} are supported, but only mentioned under Other commands. Q: system. Why do I need to put a minus sign? I am a mathematics undergraduate to understand elementary physics. following exercise looks obscure me. $3.70\,\text{kg}$ (let's call $m_1$) is connected to a $2.30\,\text{kg}$ mass (let it be $m_2$) a massless and inextensible rope, which is bent by a in figure below. I to compute the acceleration the ($a$) and the tension rope By reference for mass (as the picture I worked out the following for the forces acting
iber).
But I need something else
unfortunatEly, thIs iS alL bIblaTex oFfers at the momeNT.
You Can't have per-field languaGe swiTcHIng wITh PossiBly diffEReNT LanGuAgEs pEr ENtRy (see HttPs://githuB.com/plk/bibLatEx/Issues/895).
It is soRT oF possible, bUt qUite tricky, to SwiTch onlY tHe fIEld coNteNts to <Langid> LEaving The rest (biBsTRings, pUNctuatiON) In The mAin document languaGE (tHIs works around tHe issuEs MEnTIOneD wiTh autolang=HyPhen aBOve). See CHAnGE LAngUAge on a per fielD basis, part 2: FONts, Case trAnSfoRMation And soRtINg, nOte that the iMpleMentation Has somE DrawbacKS, it does For exaMplE noT worK WiTh \makESENteNCecasE.
unfOrtunateLy, ThE implEmenTATIOn of A moRe soPhistIcated languagE swItchINg mEchanIsm loOks qUiTe comPlicatEd...
polYgLossia
I should meNtioN that biblAteX's PolYgLossiA SupporT is Not Great. biBlatex cAN't dEtECT PoLyglossia's language VaRIAnTs and thuS fails TO pRoDUce the exPeCteD datE FOrmat For bRItIsh or ausTrian (oR AuStRalian). SEe For exaMpLe \DEclAreLaNGuagEMappiNgSuffix, InherITance, and polyglOSsia in biblateX.
it SHOuLD alsO be Mentioned thAt thE PrefErreD WaY to SWitch LanguAgES aCCording to the polygloSsIa docuMentaTion seems to be \Text<languaGE>{...} FOr a few woRds aND \bEGin{<language>}...\end{<LanguAge>} for longER passageS in <laNguage>. \foReignlangUAGe{<languaGe>}{...} aNd \bEgiN{otHERlAnguage}{<languaGE>}...\End{oThErlanguAge} Are stilL suPpoRteD, buT oNly mentioNed under otHeR cOmManDs.

 Q:

PuLLey systeM. WHy dO I NeeD to puT A minus Sign?

I Am a mAtHeMAtiCs underGRaDUAte wHo'S sTrugGliNg To undErstANd eLementaRy physics. the FOlloWiNg ExercisE looks particuLaRly obscure To Me.
A $3.70\,\Text{kg}$ MASs (let's caLl it $m_1$) is connected to a $2.30\,\text{KG}$ mass (leT it Be $m_2$) thRougH a masslesS anD inextEnsIBle ropE, which Is benT bY a pULLey liKE In The FiGure below.

I NEEd tO compUtE the AccelerAtion of the masses ($a$) aND thE tension of the RopE ($T$). By CONsIdeRInG Two DiFFerENT reference frameS for each maSs (AS tHe picture sHOws), i wOrked ouT the folLowinG EquatioNs for the fOrces actiNg On $m_1$ aLONg iTs $
iber).
But I need somethin g else
Unf ortun ate ly,  t hisis a ll biblatex of f ersat the moment.
You can 't ha ve per- f ie ld la nguages wi t c hin gwi thpo s si bly d iff erent l anguages p eren try (see htt p s: //github.c om/ plk/biblatex /is sues/8 95 ).I t issor t ofpossib l e, but  quite tr ic k y, tos witch o n l ythefield contents to <l a ngid> leavingthe re st (b i b str ing s, punctua ti on) i n  the ma i nd o c ume n t language (t his works a r oun d theis sue s  menti onedwi t h a utolang=hyp henabove). S ee Cha n ge lang u age ona perfie ldbasi s ,pa rt2: Fon t s,  ca s e t ransform at io n and  sor t i n g , no tethat  theimplementatio n h as s o medrawb acks,  itdo es fo r exam ple n ot  work with \Mak eSen tenceCase .
U nf ort un ately ,  the i mpl eme ntation  of a m o reso p h i st icated language sw it c h in g mechan ism lo o ks  q u ite comp li cat ed.. . polyg loss i aI should  menti o nth at bibl at ex's p ol ygl oss ia su p port  is no t great.  bibl a tex can't dete c t polyglossia ' sl a ng u agevar iants and t husf ails  top ro duc e  theexpec te d  d a te format for briti sh  or au stria n (or austral ian). Seef o r  example  \De c la r eLanguageMappi ngSuf fix, inher i tance, a nd po lyglossi a in bibl a t ex.
It s hou ldals o b e me ntioned thatt h e pr ef erred w ayto swit chlan gua ges  a ccordingto the p ol yg lo ss iadocum e ntationse ems  t o b e \te x t<lang uage> {... }fo r  afew wor d sa n d \b eg in {<la ngu ag e>}.. .\en d {<l anguage >} for lo nge r  pas sa ge s in <l anguage>. \fo re ignlanguag e{ <la nguage > } {...} an d \begin{otherlanguage} { <langua ge> }...\ end{ otherlang uag e} are  st i ll sup ported , but  o nly m entio n e dund er  Other com m a nds .

 Q :
Pul ley sys tem. Why do I need toput a minus s ign ?

I a ma m a th e mat ic s  un d e rgraduate who's  strugglin gt ounderstand ele me ntary p hysics.  Thef ollowin g exercis e looks p ar ticu l a rly  obscure t o me.
A$3.70\,\t e xt{kg } $mass(le t's ca ll  it  $m_1 $) isc onn ected  to a$2 .30\,\ text{ kg }$ mass(let it be $m_2$) throu gh a m assle ssand inext ens i ble  rope, wh ichis bent by  apul ley l ike in th e fi g ur e b e low.
I n e ed to com p ut e t h e  a cceleration o f  th e mas ses ($a$)andthe tension of th e  rope ($T$). B y co n s ide rin g  two  d ifferent refer enc ef r ames for  e ach mass (a s the pi ct u re sh ows),I work ed outt h ef ollowi ng e qua tions for  th ef orces a ct in g  on $m _1$al ong it s $
iber).
But I_need something_else
Unfortunately, this is all_biblatex offers_at_the moment.
You_can't_have per-field language_switching with possibly_different languages per entry_(see https://github.com/plk/biblatex/issues/895).
It is_sort_of possible, but quite tricky, to switch only the field contents to <langid> leaving_the_rest (bibstrings,_punctuation)_in_the main document language (this_works around the issues mentioned_with autolang=hyphen_above). See Change language on a per field_basis,_part 2: Fonts,_case transformation and sorting, note that the implementation has_some drawbacks, it does for example_not work with_\MakeSentenceCase.
Unfortunately,_the_implementation of a more_sophisticated language switching mechanism looks quite_complicated...
polyglossia
I should mention that biblatex's polyglossia_support is not great. biblatex can't detect_polyglossia's language variants and thus fails_to produce the expected date_format for_british or austrian (or australian)._See for example_\DeclareLanguageMappingSuffix, inheritance,_and polyglossia in_biblatex.
It should also be mentioned that_the preferred way_to switch languages according to the_polyglossia_documentation seems to_be_\text<language>{...}_for a_few words and_\begin{<language>}...\end{<language>}_for longer_passages_in <language>. \foreignlanguage{<language>}{...} and \begin{otherlanguage}{<language>}...\end{otherlanguage} are_still_supported, but only mentioned under Other commands.

_Q:

Pulley system. Why do_I_need to put a_minus sign?

I am a mathematics_undergraduate who's struggling to understand elementary_physics. The_following exercise_looks particularly obscure to me.
A $3.70\,\text{kg}$ mass (let's call it $m_1$)_is connected to a $2.30\,\text{kg}$ mass_(let it be $m_2$)_through a_massless_and inextensible rope,_which_is bent_by a pulley like in the figure_below.

I need_to compute the acceleration of the_masses ($a$) and the_tension_of the rope ($T$). By considering_two different reference frames for each_mass (as the picture shows),_I_worked_out the following equations for_the forces acting on $m_1$ along_its $