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Question
A car is being driven by a force of 2.5 ✕ 1010 N. Travelling at a constant speed of 5 m/s, it takes 2 minutes to reach a certain place. Calculate the work done.
Solution
Force applied by the car, (F) = 2.5 × 1010 N
Speed of the car, (v) = 5 m/s
Time taken, (t) = 120 s
So distance travelled,
Distance = Speed × Time
= 5 × 120 m
= 600 m
So, Work done = (Force) × (Distance)
= `2.5 xx 10^10 xx 600` J
= `1.5 xx 10^13` J
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