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A car of mass m is driven with accelerat...

A car of mass `m` is driven with acceleration `a` along a straight level road against a constant external resistive force R. When the velocity of the car V, the rate at which the engine of the car is doing work will be

A

RV

B

maV

C

(R+ma)V

D

(ma-R)V

Text Solution

Verified by Experts

The correct Answer is:
C
Force required to move with constant velocity
`therefore` Power= FV
Force is required to oppose the resistive force R and also to accelerate the body of mass with acceleration a.
`therefore` Power `= (R+ ma)V`
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ERRORLESS -WORK , ENERGY , POWER AND COLLISION-Ordinary Thinking (Objective Questions) (Power)
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