Lab 1: Fermi Problems and Air Tracks


Fermi Problems

I'm looking for estimates, not precise answers! You should round off with reckless abandon, and avoid using a calculator if at all possible. Do these problems in your groups, and hand in your solution.
  1. Estimate the number of piano tuners in Boston.

  2. (Due to Eric Mazur.) On a Saturday afternoon, you pull into a parking lot with unmetered spaces near a shopping area. You circle around, but there are no empty spots. You decide to wait at one end of the lot where you can see (and command) about 20 spaces. How long do you have to wait before someone frees up a space?


Air Tracks

Don't worry about getting terribly precise results. However, do make velocity measurements as well as you can. For each scenario, find the velocities and check to see if momentum is conserved or not. You don't need to do these exercises in a group. Only hand in your notes for part 6.

  1. Level the air track.
  2. Take a cart and give it a shove. What happens to the cart? Explain the motion using the language of chapter C2.
  3. Reproduce the experiment discussed in Figure C2.2.
  4. Reproduce the experiment discussed in Figure C2.3.
  5. Reproduce the experiment discussed in Figure C2.5.
  6. Set up the situation used to measure mass as described in the text. Try it out using at least two different test objects. Estimate the velocities as best you can. (This probably won't be that well---don't worry about it.) Then calculate the masses of the two different test objects. What units is your answer in?



[Dave] [Physics I] [COA]

Web page maintained by dave@hornacek.coa.edu.