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Question
A nut is opened by a wrench of length 20 cm. If the least force required is 2N, find the moment of force needed to loosen the nut.
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Solution
Given: Length of wrench, r = 20 cm
= 0.20 m
Force applied, F = 2 N
The force is applied perpendicular to the wrench, so
Moment of force = F × r
= 2 × 0.20
= 0.40 N m
Therefore, the moment of force needed to loosen the nut is 0.40 N m.
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