Procedure

  1. Set up the track with end stop, super pulley and photogate. (Experiment Set Up)
  2. Set up the Smart Timer to measure acceleration from the super pulley. (Setting up the Smart Timer)
  3. The track must be adjusted to compensate for friction. Set the cart on the track. Adjust the leveling screw at the end of the track to raise that end. If the cart stays at rest when placed on the track, and moves down the track with a slow steady speed after a gentle push, then the friction compensation is correct. Take care with this as small changes in the slope have noticeable effects on the accelerations.
  4. Use the balance to find the mass of the cart and record the mass.
  5. Place the cart on the track so the spring plunger will bounce off the end stop, attach a string to the hole in the end of the cart, and tie a mass hanger on the other end of the string
    Note 1: The hanger masses can range between 20 and 50 g in 5 g steps
    Note 2: The string must be just long enough so the cart hits the end stop before the mass hanger reaches the floor.
  6. Pull the cart back until the mass hanger reaches the pulley. Make a test run to determine how much mass is required on the mass hanger so that the cart takes about 2 seconds to complete the run.
  7. Pull the cart back until the mass hanger reaches the pulley. Release the cart from rest, and activate the Smart Timer just a moment later. (The timing will begin when the photogate beam is first blocked.) Repeat this measurement 4 more times with the same masses. Record all the values.
  8. Calculate the average accelerations and record.
  9. Increase the mass of the cart by 0.5 kg and repeat steps 4 to 8. Do not exceed 2.5 kg.