Newton's Three Laws

In our daily life we see the body being at rest, at constant motion or in acceleration. Now, Newton explains about these state of body in his three law of motion.

Newton, in his first law of motion, states, "Every object continues in its state of rest or of uniform motion along a straight line unless an external force acts on it". It explains about the inertia possesses by every object. The body at rest will continue the state of rest if an external force is not applied and this is inertia of rest. Again the body at motion will continue in the state of motion with constant speed along the direction in straight line if an external force is not applied and this is called inertia of motion.

Now, think what will happen if an external force is applied? Yes, if an external force is applied, then Newton's first law becomes Newton's second law. Thus he states in second law as, "The force acting on a body is directly proportional to the product of the mass of the body and the acceleration produced in the body by the action of the force, and  it acts in the direction of the force". If an external force is  applied to the body of rest or constant motion it gains acceleration depending upon the mass of that body. This is second law.
Again think, what will happen to the force if it will not be able to produce sufficient acceleration when applied on a body of constant motion or rest. Yes, surely second  law of Newton becomes third law of motion. But how ? It is because the force applied is balanced by the reaction produced in the body directed to the applied force. Thus Newton states "To every action there is equal and opposite reaction".

In fact, Newton's three laws of motion are interrelated to each other and one generates the other in some especial conditions.

Amar Thakuri
amr.thk49@yahoo.com