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Question
A pair of bullocks exerts a force of 140 N on a plough. The field being ploughed is 15 m long. How much work is done in ploughing the length of the field?
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Solution
Given: Force F = 140N
Displacement s = 15m
Work done = Force × Displacement
W = F × s
W = 140N × 15m
= 2100 Nm
= 2100 J
Work done in the end = 2100 J
Hence, 2100 J of work is done in ploughing the length of the field.
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