It is the product of the net force and the time interval of the contact.

The statement you provided describes the concept of impulse in physics. Impulse is the product of the net force applied to an object and the time interval during which the force is applied. It is given by the formula:

Impulse = Force x Time

This concept is crucial in understanding how changes in momentum occur. When a force is applied to an object for a certain period of time, the momentum of the object changes. This is often observed in real-world scenarios such as a bat hitting a ball, a car collision, etc.