Amandla Kinetic: yencazelo ifomula. Thola energy kinetic yezinhlayiya, ezinyakazayo Translational, entwasahlobo, umzimba, ama-molecule igesi?

nakho nsuku zonke kubonisa ukuthi impahla umzimba zingasuswa, futhi eshukunyiswa ukuyeka. Singabantu hlale sinokuthile esingakwenza emhlabeni wonke ibizwa ophithizelayo, ilanga likhanya ... Kodwa lapho akazange umuntu, isilwane, futhi ngokwemvelo ngokuvamile zivela amandla ukuba benze lo msebenzi? Kungakhathaliseki ubalekela ukunyakaza mechanical benganakwa? It uzoqala ukuthutha uma umzimba umunye ngaphandle kokushintsha nezinye traffic? Konke lokhu kuzoxoxwa ngakho esihlokweni sethu.

Umqondo amandla

Ngomsebenzi wokugqokwa injini, okuyinto lidlulisele ukunyakaza izimoto, kogandaganda, amakhanda, ezindizeni badinga fuel okuyinto umthombo wamandla. imishini kagesi lidlulisele ukunyakaza esebenzisa ugesi. Ngenxa yamandla yamanzi bokuwa usuka endaweni ephakeme, hydroturbine ujike uxhumekile imishini kagesi, odala i kagesi. YoMuntu akhona futhi umsebenzi, futhi kudingeka amandla. Bathi ukuze, ukuze enze ezinye uhlobo umsebenzi, udinga amandla. Kuyini amandla?

• Okubukwa 1. Phakamisa ibhola ngaphezu komhlabathi. Ngesikhathi yena isebujameni enokuthula, umsebenzi mechanical is hhayi lwenziwa. Makahambe. Ngaphansi kwethonya gravity ibhola phasi endaweni ephakeme ezithile. Phakathi kuwa ibhola wenziwa umsebenzi lokukhanda.
• Okubukwa 2. somknite entwasahlobo, thina ukukulungisa futhi ubeke intambo ku entwasahlobo slug. Umlilo intambo, entwasahlobo amanga flat futhi aphakamise isisindo yensimbi ezingeni ukuphakama ethile. Spring umsebenzi mechanical kwenziwa.
• 3. Ukuqaphela Sibona kuzolungisa induku nge block ekupheleni. Ngemva block perekinem ngentambo, komunye umkhawulo okuyinto nilimaza ku-eksisi Sibona bese kwelinye bob uyahlanganyela. Ake uhambe we Sinker. Ngaphansi kwethonya adonsela phansi , yena eliyocwila ukunikeza inqola. Bob kwenziwe umsebenzi lokukhanda.

Ngemva kokuhlaziya konke okwashiwo ngenhla, singaphetha ngokuthi uma umzimba noma imigwamanda eziningana ukuxhumana phakathi umsebenzi mechanical wenziwa, kuthiwa babe amandla mechanical noma amandla.

Umqondo amandla

Amandla (kusukela lesiGreki elithi amandla -. Imisebenzi) - ubukhulu ngokomzimba ephawula ikhono izidumbu 'ukwenza umsebenzi. Iyunithi amandla, futhi usebenza ohlelweni SI ingenye Joule (J 1). Amandla incwadi okhonjiswe incwadi E. Kusukela ucwaningo ngenhla, kusobala ukuthi umzimba wenza umsebenzi lapho bedlula esimweni esisodwa kuya kwesinye. lapho umzimba amandla kuyahlukahluka (incipha), futhi umsebenzi awayindwayo elilingana umphumela ushintsho ngamandla alo mechanical okwenziwa mzimba.

Izinhlobo amandla lokukhanda. Umqondo amandla ezingaba

Hlukanisa 2 izinhlobo amandla mechanical: zivele futhi kinetic. Manje sihlolisise bezikhali amandla.

Amandla ezingaba (PE) - iyona energy kunqunywa Isimo eyisihlobo nemizimba bangahlanganyela noma izingxenye zomzimba uqobo. Njengoba wonke umzimba futhi umhlaba ukuheha nomunye, okungukuthi, uxhumana, PE umzimba nezishiwo ngenhla phansi, kuzoya ukuphakama h lift. Ayanda umzimba ophakamayo, kulapho PE yakhe. Yasungulwa Ucwaningo ukuthi PE akuxhomekile nje kuphela esimweni ukuphakama lapho kuvuswa, kodwa futhi ku isisindo emzimbeni. Uma umzimba avuselwa lobulinganako, umzimba kokuba mass emikhulu uzoba mkhulu futhi PE. Ifomula amandla kanje: E _n = mgh wherein E _n - kuyinto amandla ezingaba, m - mass umzimba, g = 9,81 H / kg, h - ukuphakama.

Neqiniso lokuthi amandla entwasahlobo

Amandla bezikhali umzimba elastically zikhubazekile ngokuthi ukubaluleka ngokomzimba E _{f okuyinto} lapho ukulungisa ijubane lokuya Translational ngaphansi isenzo amabutho nokunwebeka incipha ncamashi njengoba kwenziwa kinetic namandla iyakhula. Springs (njengabanye umzimba elastically zikhubazekile) ube PE, okuyinto ilingana isigamu umkhiqizo k ukuqina ukuze ukusonteka sikwele: x = Kx ^2: 2.

amandla Kinetic: ifomula kanye nencazelo

Ngezinye izikhathi ukubaluleka kokusebenza mechanical kungabonwa ngaphandle ukusetshenziswa imiqondo amandla kanye nezithombe ezinyakazayo, ukugxila yokuthi umsebenzi limelela ushintsho amandla omzimba. Zonke ukuthi singadinga - iyona mass umzimba futhi kwaqala nesivinini ekupheleni ezokwenza usiholela energy kinetic. I energy kinetic (KE) - amandla ezibangelwa umzimba ngenxa ukunyakaza kwabo.

amandla Kinetic umoya, isetshenziswa kakhulu ukungadluliseli ezinyakazayo ophephela abaphehla ugesi. Beqhutshwa nenqwaba emoyeni nangaphansi kokucindezeleka indiza ezigobile umoya ephendulwa izimpiko, futhi ukubaphoqa ukuba baguquke. Ukuzungelezisa ngu system yokudlulisela ukudluliswa indlela enza umsebenzi othile. Beqhutshwa amanzi, iyakunqanda amandla ophephela, ulahlekelwa ingxenye CE yayo, ukwenza umsebenzi. Flying okusezingeni eliphezulu indiza esibhakabhakeni, ngaphezu PE, CE. Uma umzimba usesimweni ziphumule, okungukuthi, velocity yayo ehlobene Umhlaba zero, futhi CE yayo okuphathelene nomhlaba zero. Yasungulwa Ucwaningo ukuthi maningi isisindo futhi ijubane ngawo ihamba, kulapho-ke TBE. Ifomula we energy kinetic we ezinyakazayo Translational ku isibalo sezibalo simiswe ngalendlela lelandzelako:

Lapho K - energy kinetic, m - isisindo, v - isivinini.

Ushintsho energy kinetic

Njengoba izinga ukunyakazisa umzimba variable kuye kukhethwa uhlelo inkomba, value CE umzimba futhi kuxhomeke Ukukhetha yayo. Ushintsho energy kinetic (Ike) umzimba kwenzeka ngenxa isenzo emzimbeni bebutho zangaphandle F. _? Ubuningi ngokomzimba okuyinto _ilingana E Ike umzimba ngenxa ibutho isinyathelo F, shayela operation: A E = _k. Uma isigungu esiletha ihamba ngesikhathi v isivinini _1, amandla F, okuyinto kuvumelana isiqondiso, the velocity ukunyakaza komzimba iyokwanda esikhathini isikhathi t kunani ezithile v _2. Kulokhu, u-Ike kuyinto:

Lapho m - nenqwaba umzimba; d - indlela siwela umzimba; V _F1 = (V ₂ - V _1); V _F2 = (V ₂ + V _1); a = F: m. Kungenxa yalesi ifomula ibalwa, kangakanani kinetic namandla washintsha. Formula nalo nencazo ezilandelayo: _I-E = Flcos ά, lapho cosά kuyinto igebe eliphakathi zithwala force F kanye V _Isivinini?

Isilinganiso energy kinetic

amandla Kinetic iyona energy kunqunywa ijubane amaphuzu ezahlukene okungokwendlela lesi simiso. Nokho, qaphela ukuthi kubalulekile ukuba bahlukanise phakathi amandla ezimbili agcwele ezahlukene izinhlobo ukunyakaza: Translational futhi ukujikeleza. Isilinganiso energy kinetic (SKE) kulesi simo umehluko isilinganiso phakathi amandla Imininingwane lonke uhlelo namandla alo kwengqondo, okungukuthi, eqinisweni, usayizi waso - kuba nenani isilinganiso the engaba namandla. isilinganiso energy kinetic Ifomula:

lapho k - iyona Boltzmann njalo; T - lokushisa. Kuyinto lokhu kwesibalo siyisisekelo kwemfundiso yokuziphendukela yamangqamuzana-kinetic.

Isilinganiso energy kinetic yezinhlayiya igesi

ucwaningo oluningana luye lwembula ukuthi amandla isilinganiso kinetic yezinhlayiya igesi kule nhlangano phambili ezingeni lokushisa enikeziwe okufanayo futhi akuxhomekile uhlobo igesi. Ngaphezu kwalokho, kwatholakala ukuthi Ukushisa igesi ^cishe 1 C SKE is abaqhubeke ngomunye futhi anenani elifanayo. Okuningi ngokunembile, inani kuyinto :? E _k = 2,07 x 10 ^-23 J / ° ^C. Ukuze abale yini amandla isilinganiso kinetic yezinhlayiya igesi entuthukweni, kubalulekile, ngaphezu kwaleli nani isihlobo, ukwazi okungenani eyodwa ngaphezulu inani eliphelele ukunyakaza Translational zamandla. Ngo-physics, amanani anhlobonhlobo okushisa kunqunywa ngokwanele ngokunembile. Ngokwesibonelo, ngo-t = 500 ^{° C} amandla kinetic ukunyakaza Translational Ek-molecule = 1600 x 10 ^-23 J. 2 Eqaphela izinzuzo (? E _k no-E _k), singakwazi ukubala amandla njengoba ngokunyakaza Translational yezinhlayiya ezingeni lokushisa esinikeziwe, futhi ukuxazulula inkinga ephambene - ukunquma lokushisa phezu sesethi yamanani amandla.

Ekugcineni, singaphetha ngokuthi amandla isilinganiso kinetic yezinhlayiya, ifomula okuyinto eboniswe ngenhla kuncike kuphela izinga lokushisa ngokuphelele (kanye nanoma yisiphi isimo wokuhlanganisa zezinto).

Umthetho ukulondolozwa amandla Imininingwane mechanical

Ukutadisha ezinyakazayo zemizimba ngaphansi isenzo gravity kanye amandla nokunwebeka wabonisa ukuthi kukhona ubuningi ngokomzimba othiwa ezingaba amandla E _n; incike uzimele umzimba, futhi ushintsho yayo ulinganiswa Ike, esithathelwe uphawu okuphambene: Δ E _{n =} - _E?. Ngakho, inani CE futhi PE izinguquko emzimbeni, okuyinto ukubambisana amandla adonsela phansi futhi amabutho nokunwebeka kuyinto 0:? Δ E _n + E _k = 0. Amabutho encike kuphela izixhumanisi emzimbeni, abizwa ngokuthi olandelanayo. Amandla ezikhangayo futhi kuyaqina zizinto olandelanayo. Isamba energy kinetic abangaba somzimba amandla Imininingwane mechanical: E _n + _k = E E.

Leli qiniso, eye kungase kutholakale ucwaningo olunembile kakhulu,
ngokuthi umthetho ukulondolozwa amandla lokukhanda. Uma umzimba uxhumana amabutho, okuyinto kuxhomeke Isivinini isihlobo, amandla mechanical uhlelo zemizimba uxhumana ingagciniwe. Isibonelo amabutho zalolu hlobo, ababiziweyo non-ngoludala, ungamandla friction. Uma isinyathelo umzimba amandla kokukhuhlana, kubalulekile ukuba azinqobe ukusebenzisa amandla ukuthi kuyingxenye isetshenziswa ukwenza umsebenzi nendikimba friction. Nokho, umthetho ukulondolozwa amandla angaqondakaliyo kuphela, ngoba icala ekhethekile yomthetho jikelele kwemvelo kanye ukuguqulwa wamandla. amandla umzimba alipheli futhi liphinde likhulume ngoBharuki: yena kuphela aguqulwa kusuka ifomu eyodwa kuya kwenye. Lokhu wemvelo kubaluleke kakhulu, kwenziwa yonke indawo. Futhi ngezinye izikhathi obizwa ngokuthi umthetho jikelele kwemvelo kanye ukuguqulwa wamandla.

Ukuxhumana phakathi amandla zomzimba zangaphakathi, le kinetic namandla ezingaba

Amandla zangaphakathi (U) zomzimba - kuba namandla akhe egcwele umzimba lokususa emzimbeni EC sisonke PE yayo amandla zangaphandle emkhakheni. Kule singaphetha ngokuthi amandla yangaphakathi siqukethe TBE ezinyakazayo okungahleliwe zishintshe, ukuxhumana phakathi PE futhi vnutremolekulyarnoy amandla. amandla Yangaphakathi - umsebenzi owodwa awusizo isimo uhlelo, ukuthi uthi lokhu okulandelayo: uma uhlelo kulesi sifundazwe, amandla layo langaphakathi uthatha inani layo esingokwemvelo, kungakhathaliseki ukuthi kuvelani ngaphambili.

relativism

Lapho ijubane umzimba eduze Isivinini ukukhanya, energy kinetic kutholakala le ndlela elandelayo:

I energy kinetic yomzimba, ifomula eye wawulotshwe ngenhla uthi, kungabuye ibalwa isimiso elandelayo:

Izibonelo zezinkinga ukuthola energy kinetic

1. Qhathanisa kinetic namandla ibhola enesisindo 9 g, flying ngesivinini 300 m / s, futhi umuntu enesisindo kg 60, egijima ngesivinini 18 km / h.

Ngakho, yini siye enikeziwe: m ₁ = 0.009 kg; V ₁ = 300 m / s; ₂ m = 60 kg, V ₂ = 5 m / s.

isixazululo:

• amandla Kinetic (EQ) _E = mv ^2: 2.
• Sinazo zonke idatha sokubalwa, futhi ngenxa yalokho _ukuthola E futhi umuntu futhi ibhola.
• E = _K1 (x 0,009 kg (300 m / s) ²⁾ 2 = 405 J;
• _K2 = E (x kg 60 (5 m / s) ²⁾ 2 = 750 J.
• E _K1

Impendulo: I-energy kinetic ibhola lingaphansi kuka womuntu.

2. Umzimba 10 kg wavuselwa ukuphakama 10 m, ngemva kwalokho-ke wadedelwa. Yini EC kuyoba ezingeni ukuphakama 5 m? Air ukumelana ovunyelwe ukuba singasinaki.

Ngakho, yini siye sanikelwa: m = 10 kg; h = 10 m; ₁ h = 5 m; g = 9,81 N / kg. E _K1 -

isixazululo:

• NgoLwesine kutholakale isidumbu sendoda mass unikezwa, ephakanyiswe ukuphakama ethile, ikhono amandla: E _p = mgh. Uma umzimba uwela, kuba ezingeni ukuphakama ethile h ₁ kuyodingeka izithukuthuku. amandla E = mgh _{isimangalo 1} futhi Kin. amandla E _K1. Ukuze bathole energy kinetic formula, eye eboniswe ngenhla kahle, akusebenzi, ngakho ukuxazulula inkinga ngokuvumelana algorithm elandelayo.
• Kulo sinyathelo, usebenzisa umthetho ukulondolozwa amandla, futhi ngeke sikwazi ukubhala: E _n1 + E _K1 = E _n.
• Khona-ke u _K1 = E _n - E _n1 = mgh - mgh ₁ = mg (hh _1).
• Uma kufakwa yamanani ifomula yethu, sithola: E = 10 x _K1 9,81 (10-5) = 490,5 J.

Impendulo: E _K1 = 490,5 J.

3. twin mass ligcina uthi lokuphotha luzungeza kokuba m mass engaba R, lena ezizongolozele i-eksisi edabula phakathi nendawo. Evala Isivinini emincane ye ligcina uthi lokuphotha luzungeza - ω. Ukuze umise ligcina uthi lokuphotha luzungeza ukuze kondi lwalo icindezelwa ngokumelene izicathulo ukubopha siphile ngokuvumelana nalo nge _ngomshikisho amandla _F. Bangaki linemibhikisho uyokwenza ligcina uthi lokuphotha luzungeza yokuma? Cabangela ukuthi isisindo ligcina uthi lokuphotha luzungeza igxile usebe.

Ngakho, yini siye sanikelwa: m; R; ω; F _{ukuhilizisana.} N -?

isixazululo:

• Ekuxazululeni izinkinga bayocabanga enjalo umfutho ligcina uthi lokuphotha luzungeza uphendulela eyohlobo ayindilinga mncane nge R engaba kanye m mass, okuyinto uphendulela nge emincane Isivinini ω.
• I energy kinetic somzimba ilingana: E _a = (J ω ²⁾ 2, lapho J = m R ^2.
• Ligcina uthi lokuphotha luzungeza eyeka ngaphansi kombandela wokuthi yonke yayo esichithwa umsebenzi TBE izithathe ukuze ixazulule leyo ngomshikisho amandla F _{ukuhilizisana ephakathi} isihlangu wazihlephula, usebe: _E = F _ngomshikisho * _s, lapho s - kuyinto ibanga kokusebenza, okuyinto ilingana 2 πRN.
• Ngakho-ke, F * 2 _Friction πRN = (M R ² ω ²⁾ 2 lapho N = (m ω ² R): (4 π F mp).

Impendulo: N = (mω ² R): (4πF _mp).

Ekuphetheni

Amandla - iyisici esibalulekile kuzo zonke izici zokuphila, ngoba ngaphandle kwalo, akukho emzimbeni ngeke akwazi ukwenza umsebenzi, kuhlanganise nabantu. Sicabanga ngalesi sihloko ngokucacile ukuthi amandla, futhi incazelo eningiliziwe zonke izici omunye izingxenye zalo - amandla kinetic - kuzokusiza uqonde izinqubo eziningi ezenzeka kule mbulunga yethu. Futhi indlela yokuthola energy kinetic, ungafunda esibonelweni amafomula nokuxazulula izinkinga okungenhla.