15 Examples of Newton’s Third Law of Motion

Sir. Isaac Newton’s three laws of motion explain the effect of force on an object. It is often said that every action is followed by a reaction. This is true for forces in physics. Newton’s third law explains the reaction of an applied force. This law is also known as the law of action and reaction. In this article, we discuss 20 examples of Newton’s first law of motion.

Newton’s third law statement

We can state Newton’s third law as:

For every action (force applied), there is an equal and opposite reaction (reaction force).

This law explains how forces are balanced in nature by an equal and opposite force. This law gives us the magnitude and direction of the reaction force, which is useful in the numerical computation of forces.

Newton’s third law of motion examples

Examples of Newton’s third law are more visible to us in nature and our daily lives. We encounter such examples every moment in our lives. The very reason we are able to sit, stand, and walk is due to reaction forces from the ground. You can also read our articles on examples of Newton’s first and second laws of motion.

  • Pulling an elastic band
  • Swimming or rowing a boat
  • Static friction while pushing an object
  • Walking
  • Standing on the ground or sitting on a chair
  • The upward thrust of a rocket
  • Resting against a wall or tree
  • Slingshot
  • Slapping
  • bouncing of ball
  • Jumping on a trampoline
  • Hitting off a ball by a bat
  • When you run on a carpet, it moves backward
  • When pushing someone or pushing something, we tend to move backward
  • The recoil of a gun

Let us discuss each of the examples in detail and see how they are consistent with Newton’s third law of motion.

Pulling an elastic band: When we pull an elastic band, it automatically returns to its original position. The more you pull, the more force it generates. This is the same when you pull or compress a spring. The action (applied force) is stored as energy and is released as a reaction with an equal and opposite force.

Swimming or rowing a boat: When swimming or moving in a roving boat, you have to push the water backward in order to move forward. The generated in the backward direction gives an and opposite reaction in the forward direction. The more you push back the more you move forward.

examples of newton's third law of motion
Rowing is an example of Newton’s third law of motion. Image by Kira Phạm from Pixabay 

Static friction while pushing an object: Sometimes when you apply a force, nothing happens. Let us take the example of static friction in which Newton’s third law is not followed. When we push a heavy object, say a rock, nothing happens. There is no reaction force for the force applied to it. There is actually a reaction force supplied by the rock in the static friction. This static friction force helps it resist your force and stay in place. This force is self-adjusting, so it adjusts itself to be equal and opposite to applied force.

Walking: While we walk, we apply a force in the backward direction, and in response, the friction provides an equal and opposite force that helps us to move forward. In essence, if there was no friction, we could not walk. You can read our blog on friction as a necessary evil to know more about this.

Action-reaction forces, while we walk, is an example of Newton’s third law

Standing on the ground or sitting on a chair: Whenever we stand or sit or lie on the ground we feel nothing. But there is actually a reaction force from the ground which counters the weight of our body. The action here is our body weight, and the reaction force is a force from the ground to support us.

Slingshot: When we pull a slingshot the energy gets stored in the elastic material. And when we release the slingshot we get an equal and opposite force that is able to propel the object. Here the direction in which we pull is also important as that will determine the direction in which the object will travel.

Punching an object: When we punch an object or kick something, the object may break due to our force which is an action. But we also get a force onto our hands and legs as a reaction force. That is why you feel pain after slapping someone or punching a wall.

Resting against a wall or tree: When we rest against a tree or a wall, we get a reaction force from the tree or the wall in order to support us. You can understand this example by imagining if someone is to rest on you then you have to apply some force to support the other person. This example of Newton’s third law is also an example of balanced forces.

The upward thrust of a rocket: A rocket is able to escape the gravitational force of the Earth because of its high velocity. This velocity is calculated to exceed the escape velocity. But how is such a high velocity possible? This is based on action-reaction forces. The exhaust from the rocket creates a downward force which creates an equal and opposite thrust in the upward direction.

escape velocity-action reaction forces
The exhaust of the rocket is able to get a reaction force in the upward direction.

Bouncing ball: A ball is able to bounce because of the reaction from the ground. If there was no reaction then the ball would not bounce but rather stick to the ground.

Jumping on a trampoline: We are able to jump on a trampoline due to the reaction force from the elastic material.

Basketball hitting the board: When a basketball hits the board it comes back with almost an equal force at which thrown. The throwing action resulted in an equal and opposite force from the board.

When you run on a carpet, it moves backward: Try running on a carpet carefully, you might notice that the carpet starts to move backward, this is the reaction force in the opposite direction.

Pushing someone or pushing something we tend to move backward: When we push someone we tend to move back a bit due to the reaction force we receive from the person.

Diving: When someone is diving from a diving board, you can clearly see the reaction force in the board in the way it vibrates after the jump. The action force is the muscular force by the legs of the diver and the reaction is the jump by the diver and also the vibration of the board.

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