question_answer

  The earth and the moon are attracted to each other by gravitational force. Does the earth attract the moon with a force that is greater or smaller or the same as the force with which the moon attracts the earth? Why?                                                     [NCERT]

Answer:

                  The force of attraction of earth on moon is same as the force of attraction of moon on earth. The reason is that if we consider earth-moon system; then the forces exerted by them on each other are the internal forces. According to Newton's third law, the action-reaction forces have equal magnitude and opposite directions; so the force exerted by the earth on moon is equal to the force exerted by moon on earth.