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An engine develops 10 kW power. How much...

An engine develops 10 kW power. How much time will it take to lift a mass of 200 kg to a height of 40 m ?

A

10 s

B

8 s

C

5 s

D

4 s

Text Solution

Verified by Experts

The correct Answer is:
b
p=10 KW=10,000 Walts., m=200 kg, `g=10m//s^(2)`.
h=40 m
`:.` Work done, W=Mgh
=`200xx10xx40=80,000` J
Now `p=W/timplies t=W/p=(80,000)/(10,000)=8 sec`.
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