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Question
A man moves on a straight horizontal road with a block of mass 2 kg in his hand. If he covers a distance of 40 m with an acceleration of 0⋅5 m/s2, find the work done by the man on the block during the motion.
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Solution
Given:
\[\text{ Distance coverd by the man, s = 40 m } \]
\[\text{Acceleration of the man, a = 0 . 5 m} / s^2\]
\[\text{ F = ma } \]
\[ = 2 \times \left( 0 . 5 \right)\]
\[ = 1 N\]
\[\text{ Work done by the man on the block, } W = F \cdot S\]
\[ = 1 \times 40\]
\[ = 40 J\]
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