A motor car of mass 2500kg accelerates from rest to a speed of 20ms-1 in 5 s on a level road . Find the average power of the car...
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PHY 物理問題 Mechanism
2008-04-10 4:15 am
回答 (2)
2008-04-10 4:18 am
✔ 最佳答案
Gain in kinetic energy of the car, E = 1/2 mv2
= 1/2 (2500)(20)2
= 500 000 J
Average power of the car, P
= E / t
= 500 000 / 5
= 100 000 W
= 100 kW
參考: Myself~~~
2008-04-10 6:56 am
The average velocity of the car=20/5
=4ms^-1
The average power of the car=2500*4=10000W
=4ms^-1
The average power of the car=2500*4=10000W
收錄日期: 2021-04-24 10:49:03
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20080409000051KK02368