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Question
A car of weight 20000 N climbs up a hill at a steady speed of 8 m/s, gaining a height of 120 m is 100 s. Calculate : work done by the car.
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Solution
Weight of the car, (W) = 20000 N
Height, (h) = 120 m
Time taken, (t) = 100 s
We can calculate the work done against gravity as,
Work done by the car = Weight of body × Vertical distance
= 20000 × 120 J
= 2400000
= `2.4 xx 10^6` J
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