# Question

A sprinter of mass 65.0 kg starts his race by pushing horizontally backward on the starting blocks with a force of 200 N.

(a) What force causes him to accelerate out of the blocks: (1) his push on the blocks; (2) the downward force of gravity; or (3) the force the blocks exert forward on him?

(b) Determine his initial acceleration as he leaves the blocks.

(a) What force causes him to accelerate out of the blocks: (1) his push on the blocks; (2) the downward force of gravity; or (3) the force the blocks exert forward on him?

(b) Determine his initial acceleration as he leaves the blocks.

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