**Force-Time Graphs**

A force-time graph will have force (N) on the vertical axis and time (s) on the horizontal. The area under a force-time graph is , which is the impulse the object will experience during that time interval (). Recall that impulse is equal to the change in momentum of an object.

**Example 1:**

The force acting on an object over a 15 second interval is shown below:

a) Determine the force acting on the object at seconds:

At seconds,

b) When was a constant force acting on the object:

Between and

c) Calculate the total impulse acting on the object over the 15 second interval:

The total impulse acting on the object = the area under the graph. It is convenient to divide the graph into several rectangles and triangles and then calculate the sum of these areas:

Area A =

Area B =

Area C =

Area D =

Total area =

Therefore, Impulse,