Question

What is the effect of a force on the momentum of an object? Hence define Newtons 2nd law of motion.

Answer 1

The bigger force is applied on a body of given mass, its linear momentum changes faster and vice - versa. The momentum will change in the direction of the apllied force.
According, to Newton's IInd law of motion, the rate of change of linear momentum of a body is directly proportional to the external force applied on the body, and this change takes place always in the direction of the applied force.