FORCE AND LAWS OF MOTION, Class IX, Part 4
If a boy wearing roller skates stands facing a wall and pushes the wall with his hands, the boy finds himself moving backward, away from the wall. It appears as if the wall also pushes the boy away. When the boy exerts a force on the wall by pushing it with his hands, then the wall exerts an equal force on the boy in the opposite direction . Since the boy is wearing roller skates, the opposite force exerted by the wall makes him backward, the boy on roller skates is exerting force on the wall towards the left side. The wall exerts an equal force on the boy towards the right side. Due to this, the boy moves in the backward direction. From this discussion, we conclude that when a boy exerts a force on the wall, the wall exerts an equal and opposite force on the boy . This is just an illustration of Newton’s third law of motion. Whenever one body exerts a force on another body, the second body exerts an equal and opposite force on the second body. The force exerted by the firs...