Define Force and Momentum . Write the relation between them.What will happen to momentum if no force act on a body ?

Force is a push or pull upon an object resulting from the object's interaction with another object. It is a vector quantity, meaning it has both magnitude and direction. It is measured in the SI unit of Newton and represented by the symbol F.

Momentum, on the other hand, is the quantity of motion of a moving body. It is also a vector quantity and is measured in kilogram meter per second (kg.m/s). It is calculated by the product of the mass and velocity of an object and is represented by the symbol p.

The relationship between force and momentum is given by Newton's second law of motion, which states that the rate of change of momentum of an object is directly proportional to the force applied and occurs in the direction in which the force is applied. Mathematically, this can be represented as F = dp/dt, where F is the force, dp is the change in momentum, and dt is the change in time.

If no force acts on a body, according to Newton's first law of motion (also known as the law of inertia), the momentum of the body will remain constant. This means that if the body is at rest, it will stay at rest, and if it is in motion, it will continue to move in a straight line with constant velocity. This is because a change in momentum (which implies a change in velocity for a body of constant mass) requires a force. Without a force, there can be no change in momentum.