Laboratory 3: Impulse and momentum

Part 1: collision of cart with non-moving object

1. Place the track on the table and level it.  Mount a force sensor on the cart with the large rubber stopper mounted on it, and add 1-3 cart masses.  Place the motion detector at one end of the track, and the gray foam block at the other end.  Place an object (like a physics textbook) behind the foam so that it will not move or twist when hit by the rubber stopper.
2. While recording data, push the cart so it collides with the foam and comes back.  (Zero it first.) Make sure that the rubber stopper is the ONLY thing touching the foam, and that the force sensor cord is not pulling on the cart during the collision.
3. On the white board, draw the velocity and force graphs.  Also include the following data:
1. Velocity just before and just after the collision, and change in velocity.
1. Momentum just before and just after the collision, and change in momentum (impulse).
1. The area under the curve on the force graph (select “Area” under the statistics button, “S”) and the time of contact.
4. Be prepared to explain the shapes of your velocity and force graphs, and how the velocity, momentum, and area under force graphs are related.
5. For this part of your lab report, save your velocity and force diagram, and record your mass, initial and final velocities, and area under the force graph.  Also find the average force for the time of contact.

Part 2: collision with another cart

1. Remove the force sensor from your cart and put it away.  Place the second cart on the track, so that the Velcro ends are pointed toward each other, but not touching.  Place the cart masses on the carts (however you choose to place them).
2. While taking data, give the cart nearest the motion detector a push so it collides with the other.
3. On the white board, draw the velocity graph.  Also include the following data:
1. The velocity before and after the collision.
1. The momentum of each cart before and after the collision, and the total momentum.
4. For this part of your lab report, save your velocity graph and record the velocity of the cart before and after the collision, and the mass of each cart. 

Laboratory report

Part 1: use your graph and data to explain the relationship between the momentum, force and time of contact.  If there are discrepancies between numbers, you should try to identify possible sources of those.

Part 2: Use your graph and data to explain the relationship between the initial and final momentum of a system undergoing a collision.