Isimiso se-Work-Kinetic Energy

Uma amandla e-net esebenza entweni, into ithola ukusheshisa (into ithola ukufuduka). Lapho into ithola ukusheshisa, ijubane lento liyashintsha. Ngamanye amazwi, umsebenzi owenziwa amandla e-net uhlobene nesivinini sokuqala nesokugcina sento.

Umsebenzi owenziwa entweni ngamandla aphelele e-net uthi:

I-W _inethi = ΣF s

Umthetho wesibili kaNewton uthi uma kukhona amandla asebenzayo entweni, into ithola ukusheshisa.

I-W _inethi = (ma) s

Uma amandla e-net engaguquki, ukusheshisa okubonwa yi-object nakho kuyaqhubeka. Ngakho-ke, singafaka i-equation yokunyakaza okuqondile engaguquki esikhundleni sokusheshisa (a) kanye nokufuduka (s).

Isimiso se-Work-Kinetic Energy 1

Faka i-equation yokunyakaza okuqondile engalingani ku-equation yomsebenzi:

Isimiso se-Work-Kinetic Energy 2

Incazelo: EK _t = amandla okugcina e-kinetic, EK _o = amandla okuqala e-kinetic, m = isisindo, v _t = isivinini sokugcina, v _o = isivinini sokuqala

Lesi sibalo sakha i-work-kinetic energy theorem. I-work-kinetic energy theorem isazisa ukuthi umsebenzi we-net noma umsebenzi owenziwa amandla e-net entweni ulingana noshintsho lwamandla e-kinetic ento. Isazisa futhi ukuthi amandla e-kinetic ento alingana nomsebenzi we-net odingekayo ukusheshisa into isuka esimweni sokuma iye ekuhambeni ngesivinini esithile, kanye nokuphikisana nalokho.

Isibonelo sombuzo 5: Ithiyori yamandla e-work-kinetic

Imoto enesisindo esingu-1000 kg isuka esimweni sokungashukumi. Ngokuphazima kweso, ijubane liyakhuphuka lifike ku-10 m/s. Ingakanani i-net work eyenziwa yizinjini zemoto?

Isixazululo:

Kwaziwa: m = 1000 kg, v _o = isivinini sokuqala = 0 m/s (ekuqaleni, imoto iphumule), v _t = isivinini sokugcina = 10 m/s

Okufunwayo: Inethiwekhi

W _inetha = 1⁄2 m (v _t² – v _o² )

I-W _inethi = 1⁄2 (1000)(10 ² – 0 ² ) = (500)(100 – 0) = (500)(100) = 50,000 amaJoules

1. Uyini umgomo we-Work-Kinetic Energy? Umgomo we-Work-Kinetic Energy uthi umsebenzi wenethi owenziwe entweni ulingana noshintsho lwamandla ayo e-kinetic. Ngokwezibalo, $_{i-W net =} Δ_{K} E, lapho i$ - $Δ K E$ ingamandla okugcina e-kinetic ngaphandle kwamandla okuqala e-kinetic.

2. Umsebenzi uhlobene kanjani noshintsho lwejubane lento? Umsebenzi owenziwa entweni ungashintsha ijubane layo. Ngokuqondile, umsebenzi wenethi owenziwe entweni ulingana noshintsho lwamandla ayo e-kinetic, kanti amandla e-kinetic ahlobene nesikwele sejubane. Ngakho-ke, uma umsebenzi wenethi omuhle wenziwa entweni, ijubane layo (futhi ngenxa yalokho amandla ayo e-kinetic) liyakhula.

3. Kwenzekani emandleni e-kinetic ento uma kwenziwa umsebenzi ongemuhle kuyo? Uma kwenziwa umsebenzi ongemuhle entweni, amandla ayo e-kinetic ayancipha. Lokhu kungabangela ukuthi into yehle ijubane.

4. Isimiso se-Work-Kinetic Energy sihlobana kanjani nomthetho wesibili kaNewton? Umthetho wesibili kaNewton uchaza indlela amandla athinta ngayo ukunyakaza kwento, kanti isimiso se-Work-Kinetic Energy sihlobanisa umsebenzi owenziwa yileyo mandla noshintsho lwamandla e-kinetic. Yomibili le mibono ixhunyaniswe ngomqondo wokuthi amandla angashintsha isimo sokunyakaza kanye namandla ento.

5. Ingabe amandla e-kinetic ento angaba negative? Cha, amandla e-kinetic ahlala engekho negative. Anikezwa yifomula ethi $K E = 1/2 m v^{2}$ , lapho u-m eyisisindo kanti u-v uyisivinini. Njengoba kokubili isisindo kanye nesikwele sejubane kukuhle, amandla e-kinetic nawo akuhle noma awekho.

6. Umgomo we-Work-Kinetic Energy usebenza kanjani entweni ehamba ngendlela eyindilinga? Entweni ehamba ngendlela eyindilinga ngesivinini esingaguquki, amandla ayo e-kinetic ahlala engaguquki njengoba ijubane layo lingaguquki. Kodwa-ke, isiqondiso sejubane layo siyashintsha njalo. Uma kuphela amandla aphakathi nendawo (njengokucindezeleka noma amandla adonsela phansi) esebenza entweni, umsebenzi owenziwa yila mandla awu-zero njengoba esebenza ngendlela eqondile eqondisweni lokunyakaza. Ngakho-ke, akukho msebenzi we-net owenziwayo, futhi akukho shintsho emandleni e-kinetic.

7. Uma kungekho amandla angaphandle, amandla e-kinetic ento ashintsha kanjani? Uma kungekho amandla angaphandle, akukho msebenzi owenziwayo entweni, okusho ukuthi amandla ayo e-kinetic ahlala engaguquki. Lokhu kuwukubonakaliswa kokulondolozwa kwamandla.

8. Kusho ukuthini uma umsebenzi wenethi owenziwe entweni ungowe-zero? Uma umsebenzi wenethi owenziwe entweni ungowe-zero, kusho ukuthi amandla e-kinetic ento awakashintshi. Into ingase isahamba, kodwa ijubane layo lihlala lingaguquki.

9. Ingabe into ingaba namandla e-kinetic ngisho noma kungekho msebenzi owenziwe kuyo? Yebo, into ingaba namandla e-kinetic ngaphandle komsebenzi owenziwa kuyo ngesikhathi esithile. Isibonelo, into esivele ihamba esikhaleni sangaphandle (kude nemizimba yamandla adonsela phansi) izogcina amandla ayo e-kinetic futhi iqhubeke ihamba ngesivinini esingaguquki, noma ngabe akukho mandla angaphandle asebenzayo kuyo.

10. Umsebenzi owenziwa amandla angewona awokugcina izinto uthinta kanjani amandla e-kinetic ento? Umsebenzi owenziwa amandla angewona awokugcina izinto ungandisa noma wehlise amandla e-kinetic ento, kuye ngokuthi isiqondiso kanye nobukhulu bamandla ahlobene nokunyakaza kwento. Isibonelo, ukungqubuzana, amandla angewona awokugcina izinto, ngokuvamile kwenza umsebenzi ongemuhle, ngaleyo ndlela kunciphisa amandla e-kinetic ento.