Question

When a ball m is thrown upwards to a height h, the work done by the force of gravity is:
(a) mgh
(b) -mgh
(c) mg
(d) mgh2

April 7, 2024

Answer

(b) -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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Question

When a ball m is thrown upwards to a height h, the work done by the force of gravity is: (a) mgh (b) -mgh (c) mg (d) mgh2

Answer

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Flash Education

When a ball m is thrown upwards to a height h, the work done by the force of gravity is:
(a) mgh
(b) -mgh
(c) mg
(d) mgh2