Question

Explain the following terms with one example each: (a) Positive work (b) Zero work

  • Work and energy CBSE Class 9
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Answer

(a) When force acts in the direction of motion of body work done is positive. When a lawn roller is pulled forward, work done is positive.

(b) When force is perpendicular to the direction of motion, work done is zero. A porter carrying load does no work.

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