Physics
When a ball m is thrown upwards to a height h, the work done by the force of gravity is:
- mgh
- -mgh
- mg
- mgh2
Work, Energy & Power
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Answer
-mgh
Reason — When a ball m is thrown upwards to a height h, the displacement h (upwards) is opposite to the direction of force of gravity mg (downwards), so the work done by the force of gravity mg in displacement h is W = -mgh i.e., negative.
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