Physics
Third Law of Motion
Quick fact
When you walk, your foot pushes the ground backward, and the ground pushes you forward with an equal force.
Why this is interesting
Have you ever wondered why a rocket pushes back when it takes off? This is due to Newton's third law of motion, which explains how forces always come in pairs.
Read the full explanation
Understanding Third Law of Motion
Newton’s third law states that when one object exerts a force on another, the second object exerts an equal and opposite force back. This means forces always come in pairs, acting on different objects. For example, when you push against a wall, the wall pushes back with the same strength, which is why you feel resistance.
A deeper explanation
The third law explains that forces are not isolated; they exist as mutual interactions between two objects. The action and reaction forces are equal in magnitude but opposite in direction. This principle helps predict motion and balance in systems like rocket propulsion, where the expulsion of gas creates an equal force pushing the rocket forward.