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A 400 kg car attains a speed of 50 mis f...

A 400 kg car attains a speed of 50 mis from rest in 20s, The power developed in the engine will be

A

50 W

B

0.5 kW

C

5 kW

D

25 kW

Text Solution

Verified by Experts

The correct Answer is:
D
Work done Is the change In kinetic energy ` = 1/2 mv^2 - 1/2 mu^2`
Thus, `W = 1/2 xx 400 xx (50)^2 = 500000 J`
Power, `P = W/t = (500000)/20`
`=25000" watt" = 25 kW`
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