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प्रश्न
State the condition when the work done by a force is negative. Explain with the help of examples.
उत्तर
If the displacement of the body is in the direction opposite to the force, then the work done is negative.
Hence, W = - F × S
For example, when a body moves on a surface, the force of friction between the body and the surface is in a direction opposite to the motion of the body, and so the work done by the force of friction is negative.
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