In this experiment, the impulse on a cart is determined in two ways, by measuring the change in velocity and by finding the area under a force versus time curve.

A cart runs down a slightly inclined track and collides with a Force Sensor equipped with either a clay bumper, spring bumper or magnetic bumper. To determine the change in momentum (impulse), the speeds before and after the collision are recorded with a photogate. The photogate is also used to trigger the beginning of data collection for the Force Sensor. To confirm the impulse, the force versus time is plotted and the impulse is determined by finding the area under the curve.

Different shaped curves of force versus time are obtained for the different bumpers. The spring and magnetic bumpers result in nearly elastic collisions while the clay produces a completely inelastic collision. The area under the clay force curve is half the area under the spring or magnetic force curves because the cart does not rebound in the clay collision.

PASCO Advantage:
Since DataStudio is capable of having start and stop conditions, force data can be collected at a high rate during the collision, showing the force in great detail without a lot of extraneous data before and after the collision. The data collection starts when the cart passes through the photogate and ends after a set amount of time.