Physicshard · Past Paper
A boy throws a ball of mass 200g vertically upwards. It reaches a height of 5m and comes back. Total work done by the boy is:
A0 J
B10 J
C20 J
D-10 J
✓ Correct Answer: B — 10 J
The boy does work only during the throw to provide kinetic energy (equal to potential energy at the peak). W = mgh = 0.2 * 10 * 5 = 10 J.
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