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Question
An object thrown at a certain angle to the ground moves in a curved path and falls back to the ground. The initial and the final points of the path of the object lie on the same horizontal line. What is the work done by the force of gravity on the object?
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Solution
The object is displaced horizontally because the beginning and ultimate positions of an object thrown at a specific angle to the ground are on the same horizontal plane. The force of gravity on the object acts vertically downwards. Therefore, no labour is done.
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