Understanding Newton's Third Law of Motion: Action and Reaction

Understanding Newton's Third Law of Motion: Action and Reaction

Newton’s Third Law of Motion

Newton's Third Law Explained

NEWTON’S THIRD LAW OF MOTION

Newton’s third law states that ‘for every action, there is an equal and opposite reaction. They always act on two different bodies’.

If a body A applies a force FA on a body B, then the body B reacts with force FB on the body A, which is equal to FA in magnitude, but opposite in direction. FB = –FA

Examples:

  • When birds fly they push the air downwards with their wings (Action) and the air pushes the bird upwards (Reaction).
  • When a person swims he pushes the water using the hands backwards (Action), and the water pushes the swimmer in the forward direction (Reaction).
  • When you fire a bullet, the gun recoils backward and the bullet is moving forward (Action) and the gun equalises this forward action by moving backward (Reaction).