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Work and Energy — Science STD 9 — Question

Maharashtra BoardEnglish MediumSTD 9ScienceWork and Energy3 Marks
Question
When is the work done by a force on a body: (a) positive, (b) negative, and (c) zero?
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Answer

Work done by a force applied on a body is:
  1. Positive work: Positive when the force acts in the direction of motion of the body.
  2. Negative work: Negative when the force acts in the direction opposite to the direction of motion of the body.
  3. Zero work: Zero when the force acts at right angle to the direction of motion of the body.

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