Newton's first law
The first rule is as follows:
"An object remains at rest with constant velocity or remains in a state of motion until the motion of that object is changed by an external force."
This means that objects by themselves can neither start their motion, nor stop nor change direction. This type of change requires external forces. For example, when you move a tree, its leaves fall down, when a vehicle suddenly starts moving, passengers lean backwards, etc.
Newton’s Second law
The rate of change of momentum of an object is directly proportional to the force exerted on it and the momentum change is in the direction of the force applied
or
The force exerted on an object is equal to the product of the mass of the object and the force generated in the direction of the force. F = ma
Examples -
It is easier to catch a tennis ball than a cricket ball and tennis ball coming from the same velocity. A heavy hammer is used by a crotchet player to break the slab of the bricks with a hand stroke.
Newton's Thard law
When an object exerts force on another object, the force it exerts on the other object is the same force acting on that object by the other object in the opposite direction.
Rule: "Every action has the same and opposite reaction. "
In other words, it can also be said that the force is always found in the form of a couple.
Example: When a rocket is released into the sky, the rocket exerts force on the ground behind it or performs an action that causes the ground to exert or force an opposite force on the rocket causing the rocket to rise upward to lift the ground. It exerts force in response to this.
The important points of the third law of motion are the following -
In the third rule, action and reaction only mean force. A simple and explicit third law states that forces are always produced in pairs. The force exerted by object B on object A is always equal to and opposite to the force exerted by object A on object B. In the second law, there may be a misconception about action and reaction that action occurs before reaction, that is, Action is cause and reaction is effect. This type of cause-effect relationship is not there in the third rule. Force on A by B and force on A by B work at the same time. Any one of these can be called action and the other is reaction. Action and reaction forces are applied on different objects and not on the same object. Therefore, if we look at the motion of any one object (A or B), only one of the two forces is related. It is wrong to claim that the two forces combine and the resulting force to be zero. Thus speaking of the complete body of two objects, FAB (force on A by B) and FBA (force on B by A) are the internal forces of the body (A + B). Adding them gives zero force. Internal forces within an object or body of particles are discarded as pairs. It is a main fact that the second law applies to an object or to a body of particles.
The action and reaction forces are equal in magnitude and opposite in direction. But they work on different things, so action and reaction never cancel each other out.
Practical example:
When the bullet is fired from the gun, it moves backward: the gun exerts force on the bullet while dropping the bullet from the gun. According to Newton's third law of motion, the bullet exerts an equal response on the gun backwards in the opposite direction, which causes the gun to rebound and move backwards.
Newton first compiled them in his book Philosophy Naturalis Principia Mathematica. Newton used them to explain the problems related to the motion of physical objects in many places. In the third part of his book, Newton demonstrated that these three laws of motion and their universal law of gravity are capable of interpreting Kepler's laws related to the motion of celestial bodies.
Very help full to low of motion
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