ABSTRACT
In many problems, particularly those involving impact, the forces acting on particles are a function of time. In these situations, it is necessary to employ the concept of linear momentum. This chapter introduces the derivation of impulse and momentum equations, which are the first integral of the equations of motion with respect to time. It deals with the law of conservation of linear momentum. A finite change of momentum may be produced, for example, by a small force or moment acting for an appreciable interval of time or by a very large force or moment acting for a short interval of time. When the interval of time is very short, the time integral of the force is known as the impulse, and the force is known as an impulsive force. Impulsive forces occur in collisions, in explosions, in the striking of a nail by a hammer, or in the action of a pile driver.
