The third law of motion, commonly known as Newton’s third law, is one of the fundamental principles of classical mechanics formulated by Sir Isaac Newton. It states:

“For every action, there is an equal and opposite reaction.”

In other words, whenever one object exerts a force on a second object, the second object exerts an equal and opposite force on the first object. This law emphasizes the idea that forces always occur in pairs, and the magnitudes of the forces are equal but act in opposite directions.

This principle has wide-ranging applications in physics, explaining phenomena such as the propulsion of rockets, the motion of vehicles, the recoil of firearms, and many other everyday situations involving interactions between objects.

Newton’s Third Law of Motion states: “For every action, there is an equal and opposite reaction.”

This law means that whenever one object exerts a force on a second object, the second object exerts an equal and opposite force on the first object. In other words, forces always occur in pairs. This principle is fundamental to understanding the motion of objects and interactions between them in classical mechanics.

Newton’s Laws of Motion are three fundamental principles formulated by Sir Isaac Newton in the 17th century. These laws describe the relationship between the motion of an object and the forces acting on it. Here they are:

**Newton’s First Law (Law of Inertia)**:- “An object at rest stays at rest, and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced external force.”
- This law essentially states that objects will not change their state of motion (either at rest or in uniform motion) unless an external force is applied to them.

**Newton’s Second Law (Law of Acceleration)**:- “The acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass.”
- Mathematically, this is represented as $F=ma$, where $F$ is the net force applied to an object, $m$ is its ass, and $a$ is its acceleration. This law quantifies the relationship between force, mass, and acceleration.

**Newton’s Third Law (Action-Reaction Law)**:- “For every action, there is an equal and opposite reaction.”
- This law means that whenever one object exerts a force on a second object, the second object exerts an equal and opposite force on the first object. Forces always occur in pairs, and the magnitudes of the forces are equal but act in opposite directions.

These three laws provide the foundation for understanding the behavior of objects in motion and the effects of forces acting upon them. They are fundamental to classical mechanics and have applications across various fields of science and engineering.