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Newton's third law of motion

In the realm of physics, Sir Isaac Newton's laws of motion serve as the foundation for understanding the fundamental principles governing the movement of objects in our universe. Among these laws, the Third Law of Motion is particularly intriguing. It states that for every action, there is an equal and opposite reaction. This law has far-reaching implications and plays a crucial role in our daily lives.

The Concept of Newton's Third Law:

The Third Law of Motion revolves around the concept of interaction between two objects. According to Newton, when object A exerts a force on object B, object B simultaneously exerts a force of equal magnitude but in the opposite direction on object A. In simpler terms, it means that every force exerted on an object has an equal and opposite force exerted on the source of that force. This reciprocal relationship between action and reaction forms the basis of Newton's Third Law.

We know F=m \(\times\) a
Where F= force
           m=mass of the body
           a=accleation

In CGS system unit of mass is gram and unit of accleation is \(cm/s^{2}\)

Unit of force in CGS system is gram \(\times\) \(cm/s^{2}\) = 1 dyne

In SI system unit of mass is kg and unit of accleation is \(m/s^{2}\)

Unit of force in SI system is kg \(\times\) \(m/s^{2}\) = 1 newton or 1 N

1 N=1 Kg \(\times\) 1 \(m/s^{2}\)
     =\(10^{3}\) gm \(\times\) \(10^{2}\) \(cm/s^{2}\)
     =\(10^{5 }\) gram \(\times\) \(cm/s^{2}\)
     =\(10^{5 }\) dyne

Third law of motion: To every action there is equal and opposite reaction.

 If we strike on the wall with our hands, then a force is applied on the wall this force is action force and according to Newton's third law of motion to every action, there is the same and opposite reaction. The same and opposite force will be applied by the wall on the hand. And therefore hands feel pain. Action and reaction take place on two different bodies. If two same and opposite forces act on a single point in the opposite direction, then the equilibrium is established.

        If two forces \(F_1\) and \(F_2\) having the same magnitude act on a single point (p) in the opposite direction, then equilibrium will be established on point p.

Examples of Newton's Third Law:

To gain a better understanding of the Third Law, let's consider some real-life examples. When a person jumps off a diving board, they exert a downward force on the board. In response, the board exerts an upward force on the person, propelling them into the air. Similarly, when a rocket launches into space, it expels exhaust gases downward with great force. As a result, an equal and opposite force propels the rocket forward, enabling it to overcome gravity and move forward.

Another classic example is a balloon rocket. By blowing air into a balloon and releasing it, the air rushes out in one direction, causing the balloon to move in the opposite direction. This occurrence demonstrates the application of Newton's Third Law, where the expulsion of air creates a reaction force that propels the balloon forward.

The Role of Newton's Third Law in Sports:

Newton's Third Law also has significant implications in the world of sports. Take, for instance, a soccer player kicking a ball. As the player's foot strikes the ball, the force applied is transmitted to the ball. Simultaneously, the ball exerts an equal and opposite force on the player's foot. This force is what gives the player a sense of impact and control, allowing them to judge the strength and direction of their kick.
Similarly, when a swimmer pushes against the water using their arms and legs, the water exerts an equal and opposite force, propelling the swimmer forward. In sports such as skiing or skateboarding, Newton's Third Law is evident when the athletes push against the ground to gain forward momentum.

The Third Law and Everyday Life:

Newton's Third Law extends beyond the world of sports and finds relevance in our everyday lives. For instance, when we walk, our feet push against the ground, and the ground pushes back with an equal force, enabling us to move forward. When a person rowing a boat pushes the oars against the water, the water pushes back, propelling the boat forward.
The Third Law also applies to the physics of driving a car. When the tires of a car push against the road, the road provides an equal and opposite force, known as friction, allowing the vehicle to move forward. Without this force, it would be impossible for the car to gain traction and move efficiently.

    Can action and reaction generate equilibrium?

No. Action and reaction though two different forces equal in magnitude and opposite direction they can't produce equilibrium. Because in spite of having the same magnitude force and opposite direction they act on two different bodies.