Video: Yuav ua li cas peb xam cov peev xwm tshwj xeeb?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
Cov units ntawm tshwj xeeb kub muaj peev xwm yog J / (kg ° C) lossis sib npaug J / (kg K). Cov Thaum tshav kub kub muaj peev xwm thiab cov tshwj xeeb kub muaj feem xyuam nrog C = cm lossis c = C / m. Mas m, tshwj xeeb kub c, hloov qhov kub thiab txias ΔT, thiab kub ntxiv (los yog rho tawm) Q muaj feem cuam tshuam los ntawm kev sib npaug : Q=mcΔT.
Yog li ntawd, koj yuav ua li cas thiaj nrhiav tau lub peev xwm kub ntawm qhov sib tov?
Ib qho yooj yim sawv cev ntawm lub zog sib npaug kev sib npaug siv rau sib tov . Tom ntej no, mus xam tag nrho lub zog ntawm lub sib tov (Q), cov tshwj xeeb kub muaj peev xwm (C p C_{p} Cp?) yuav tsum muab sib npaug los ntawm qhov tseeb huab hwm coj (m) thiab qhov kub thiab txias (ΔT) ntawm txhua yam khoom hauv cov tshuaj.
Tom qab ntawd, lo lus nug yog, koj ua li cas thiaj nrhiav tau lub peev xwm kub ntawm qhov kev sim? Cov kauj ruam los txiav txim seb qhov muaj peev xwm kub npaum li cas.
- Muab ib lub khob rau ntawm qhov sib npaug thiab nias xoom.
- Tam sim no ntxiv cov roj rau lub beaker thiab sau qhov loj ntawm cov roj.
- Nyeem qhov pib kub ntawm cov roj.
- Txuas lub joulemeter mus rau lub rhaub dej kub.
- Lub sij hawm rau peb caug feeb.
Ntawm no, koj yuav ua li cas xam qhov kub thiab txias hloov ntawm qhov muaj peev xwm kub tshwj xeeb?
Thaum twg kub kev hloov pauv yog koom nrog, siv qhov no qauv : hloov hauv kub = Q / cm rau xam tus hloov hauv kub los ntawm a tshwj xeeb tus nqi ntawm kub ntxiv. Q sawv cev rau kub ntxiv, c yog tshwj xeeb kub muaj peev xwm ntawm cov khoom koj yog cua sov , thiab m yog qhov loj ntawm cov khoom koj nyob nraum cua sov.
Cov mis rau qhov muaj peev xwm tshwj xeeb yog dab tsi?
xam tshwj xeeb kub as c = Q / (m * ΔT). Hauv peb qhov piv txwv, nws yuav muab sib npaug rau c = -63000 J / (5 kg * -3 K) = 4200 J / (kg * K). Qhov no yog qhov raug Thaum tshav kub kub muaj peev xwm ntawm dej.
Pom zoo:
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