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Question
A boy is sitting on a chair placed on the floor of a room. Write as many action-reaction pairs of forces as you can.
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Solution
The given situation involves two action-reaction pairs of forces. They are :
(a) The action force (F = mg) with which the boy pushes the chair in the downward direction and the reaction force (F' =\[-\]mg) with which the chair exerts on the boy in the upward direction.
(b) The action force (F = (M + m)g) with which the boy and the chair push the ground in the downward direction and the reaction force (F' = (M + m)g) with which the ground exerts on the boy and the chair in the upward direction.
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