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Question
A man spends 7.4 KJ energy in displacing a body by 74 m in the direction in which he applies force in 2.5 s. Calculate the force applied.
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Solution
Work done by man = 7.4 kJ
Distance moved, S = 74 m
Work done by the man= Force x distance moved in direction of force
Work, W = F × S
7.4 × 103 = F × 74
F = `(7.4 ×10^3)/74`
F = 100 N
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