Which one of the following statements is true?

The correct answer is Option 4.

Key Points

• The Earth and the Moon attract each other with equal forces of attraction but these forces are opposite in direction.
• According to the universal law of gravitation, the force between the Earth and the Moon will be proportional to the product of both their masses and inversely proportional to the square of the distance between them.
  • This is the force by which the Earth attracts the Moon and the Moon also attracts the Earth with the same force. Since the magnitude of the force is the same, the Earth attracts the Moon and the Moon attracts the Earth equally.
  • Hence, The force of gravity of the Earth on the Moon and of the Moon on the Earth are equal in magnitude but are in opposite directions.

Additional Information

• Laws of Motion:
  • According to the first law of motion,
    • "An object at rest will remain at rest and an object moving with uniform velocity will continue to move with uniform velocity unless we apply an external force on it."
  • According to Newton's second law of motion,
    • "The rate of change of momentum of any object is directly proportional to the direction of the force applied on the object."
  • Newton's third law of motion states that,
    • ​"For every action there is always an equal and opposite reaction".