derivation of three laws of motion
1.=""> First law of motion:
It states that
“A body at rest or in motion continues to be in a state of rest or motion until and unless it is acted upon by an external force”
First law of motion gives us the idea about inertia of a body. Inertia is a property of a body which resists any change in the state of the body. Inertia means “resistance to change”.
2.=""> Second law of motion:
Newton’s second law of motion states that
“The rate of change of momentum of the body is directly proportional to the applied force and takes place in the direction in which the force acts”
Mathematically:
Explanation:
It says that whenever there is time rate of change of the momentum of the body it is because of the force applied and the effect takes place in the direction of the applied force.
3.=""> Third law of motion:
Statement of Newton’s third law
“To every action there is always an equal and opposite reaction”
This law explains that the force occurs in pair i.e. whenever there is an action there is always an equal and opposite reaction. Suppose if you pull an object then the object has a tendency to pull with an equal force in a direction opposite to the direction of applied force.
Example: Rocket- gas system-The rocket is propelled in upward direction because of the action-reaction principle.