When its engine of power 79kW is generating full power, a small single-engine airplane with mass 750kg gains altitude at a rate of 2.9m/s .
What fraction of the engine power is being used to make the airplane climb? (The remainder is used to overcome the effects of air resistance and of inefficiencies in the propeller and engine.)
?%
Power
2012-10-19 7:41 am
回答 (1)
2012-10-19 4:13 pm
✔ 最佳答案
Consider a time interval of t seconds, during this time, the plane climbs a height of 2.9t metres.Hence, gain in potential energy = 750g.(2.9t) J = 21750t J
Power used to climb = 21750t/t w = 21750 w
Fraction of power used for climbing
= (21750/79000) x 100%
= 27.5%
收錄日期: 2021-04-29 17:47:02
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20121018000051KK00641