If force  acts during short interval of time dt, the linear impulse is dt. If the force  acts from time t1 to time t2, the linear impulse is given by

Now,              

Equation (7.3) can also be rearranged as

Equation (7.4) states that the linear momentum at time t1 plus the total impulse equals

to the linear momentum at time t₂.

7.2.1 The Cotnponents of Linear Itnpulse

 If Ʃ fx dt, Ʃ fy dy, Ʃ fz dt are  the x, y, and z components of linea’ impulse, we can wdte

Ʃ fx dt = (mv _x)₂ – ( mv _x) ₂

Ʃ fy dt = (mv _y)₂ – ( mv _y) ₂

Ʃ fz dt = (mv _z)₂ – ( mv _z) ₂

The above three scalar equations can be applied independently.