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Work and Energy — Science STD 9 — Question

Gujarat BoardEnglish MediumSTD 9ScienceWork and Energy2 Marks
Question

A boy throws a rubber ball vertically upwards. What type of work, positive or negative, is done:

  1. By the force applied by the boy?
  2. By the gravitational force of earth?
✓

Answer

  1. Work done by force applied by the boy is positive because this force is in the direction of motion of the body.
  2. Work done by the gravitational force is negative because this force is against the direction of motion of the body.

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