The momentum of a body is defined as the product of its mass and velocity. Its physical symbol is 'p'.
The formula for momentum is given by
p = mv
Where,
m - the mass of the body in kg
v - velocity of the body in m/s
Therefore, the unit of momentum is expressed as the kg m/s
The momentum of a body is always associated with its motion. It is a vector quantity and it is directed in the direction of the velocity vector.
If a body is at rest, the momentum associated with the body is zero.
The momentum plays a significant role in the kinematics of the body. As similar to the energy conservation law, the total momentum of the body is conserved.
Action and reaction are equal in magnitude and opposite direction by they don't balance each other because they don't occur on the same body. Action is involved on one body and reaction is involved on another body. Hope you understood...
