Question

when does the centre of gravity lie when a boy is doing sit ups explain​

Answer 1

Explanation:

When a boy is doing sit-ups, the center of gravity keeps moving up and down. Thus the centre of gravity is not fixed while doing sit-ups. It keeps changing as the boy stands up or sits down. The weight vector passes through the base but it also keeps moving slightly.

Answer 2

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When a boy is doing sit-ups, the center of gravity keeps moving up and down. Thus the centre of gravity is not fixed while doing sit-ups. It keeps changing as the boy stands up or sits down. The weight vector passes through the base but it also keeps moving slightly.