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प्रश्न
For the following scenario, state whether the work done by gravity is positive, negative, or zero.
A person walks on a levelled road.
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उत्तर
Zero work is done.
Explanation:
When a person walks on a levelled, no work is done against the force of gravity, as the displacement of the person is normal to the direction of the force of gravity, which is vertically downwards.
संबंधित प्रश्न
When a body is placed on a table top, it exerts a force equal to its weight downwards on the table top but does not move or fall

1) Name the force exerted by the table top
2) What is the direction of the force?
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Give the units of couple.
