Forces on colliding carts
Set the Force probe on the cart, resting on the flat plate that has two threaded holes in it. Mark the two holes on the cardboard with a pen or pencil.
Punch two holes in the cardboard with your pen or pencil. Enlarge them from both sides so that a screw will just fit through.
Put the two screws first through the cardboard from the underside, and then screw them into the Force probe plate. Tighten them until the heads squeeze the cardboard a little bit. A paper clip will work as a screwdriver.
Unscrew the larger eyebolt and set it aside. Glue the bumper on the smaller eyebolt.
Connect the Force probe to your handheld computer. Refer to Technical Hints to see how to connect the cables.
Predict what the force graphs will look like if you roll the two carts toward each other. What if they have about the same velocity? What if you roll one cart toward the other which is not moving? Record (or draw) your predictions in Notes on the handheld computer.
Start the software. Set the force probe to zero. Refer to Technical Hints to see how to set the Force probe to zero. Weigh each cart by hanging it from the small eyebolt.
Make the carts equal in mass by adding some clay to one of them if needed.
With the carts horizontal, set each Force probe to zero. Refer to Technical Hints to see how to set the Force probe to zero.
Start recording. Push the carts toward each other at about the same velocity, and let them bounce back.
Try this again several times. When you get a good run, save your data to the handheld.
Look at the force graphs for both teams. Were they the same for both carts? How long did the collision take? What was the maximum force? Record your observations in Notes on your handheld computer.
