Momentum is the term which measure the quantity of motion the body has. It relies on mass the body has the velocity with which the body moves.If the mass and velocity of a body is constant Any body in motion the momentum is inbuilt in it. Hence we can define momentum as mass in motion.
The momentum formula is given by,
Momentum = mass $\times$ velocity
p = m $\times$ v.
Where, p = momentum, m = mass, v = velocity.
Momentum is a vector quantity and its SI unit of it is a kilogram meter per second (Kg m/s).