Work Energy And Power Question 186
Question: 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 is ?V?, the rate at which the engine of the car is doing work will be [MP PMT/PET 1998; JIPMER 2000]
Options:
A) RV
B) maV
C) $ (R+ma)V $
D) $ (ma-R)V $
Show Answer
Answer:
Correct Answer: C
Solution:
Force required to move with constant velocity
Power = FV Force is required to oppose the resistive force R and also to accelerate the body of mass with acceleration a.
Power = $ (R+ma)V $