Q25 of 48 Page 45

Calculate the work done by a car against gravity in moving along a straight horizontal road. The mass of the car is 400 kg and the distance moved is 2m.

Given m=400kg, d=2m

car is displaced horizontally and force (weight of the car) is


acting downward, angle between force and displacement is 90 �


∴ Work done=FscosƟ=Fscos90 �=0


Thus, work done is zero.


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