ACTION FORCE: The foot pushing on the ground.

Question

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A. REACTION FORCE: The ground pushing on the foot.
B. REACTION FORCE: The skateboard moving forward
C. REACTION FORCE: The inertia of the skateboard moves.
D.REACTION FORCE: The foot is only pushing on the ground.

Answer 1

The correct answer is:

A. REACTION FORCE: The ground pushing on the foot.

According to Newton's Third Law of Motion, for every action, there is an equal and opposite reaction. In this case, when the foot pushes down on the ground (action force), the ground pushes back up on the foot (reaction force).