Linear momentum: momentum depends on two factors:one is mass of an object and the other is its velocity.newwon used the word "mass in motion" to represent the meaning of momentum. The momentum of a body is simply defined as the product of its mass(m) and it's velocity (v). It can be stated as mass in all objects have mass,if an object is in motion,then it acquired momentum.momentum is a vector because velocity is a vector. Hence,the direction of momentum is in the direction of velocity.