1.2 Impulse

1.2 Impulse

The impulse-momentum theorem states that the change in momentum of an object is equal to the impulse applied to it. Impulse (J) is defined as the product of the force (F) applied to an object and the time interval (Δt) over which the force is applied:

J = F * Δt

The impulse-momentum theorem can be mathematically represented as:
J = Δp = p_final - p_initial
This equation implies that the impulse applied to an object causes a change in its momentum.

Physical Significance:

The theorem provides a link between force and momentum, illustrating how a force applied over a period of time can change an object's momentum. This concept is crucial in understanding collisions, where forces often act over short time intervals, causing significant changes in momentum.

Example Problem:

A force of 100 N is applied to a 10 kg object for 3 seconds. What is the change in momentum of the object?

Solution:

First, calculate the impulse:
J = FΔt = 100 N × 3 s = 300 N·s
The change in momentum Δp is equal to the impulse:
Δp = 300 N·s
So, the object's momentum increases by 300 kg·m/s in the direction of the applied force.