Pumpkin Drop Rules & Cash Contest

On Thursday October 27 or Tuesday November 1 (rain date), from 12:30 to 1:30, the Society of Physics students will drop pumpkins from the top of BAL (10 stories up or about 100 feet). Build a device to catch a pumpkin without the pumpkin going splat! Answer some questions explaining the physics of the drop and the catcher. One to two points extra credit (out of 100 for course equivavent to 10—20 points on a quiz) (depending on the quality of the pumpkin catcher and how well you answer the questions). Teams of up to four can participate.

Physics 111 Pumpkin Drop Rules:

  1. Register your team entry with me (in person or by email at chyde’at’odu.edu) by Monday Oct 21.
  2. Your pumpkin catcher should be 3 feet by 3 feet in size or larger so that the pumpkin droppers can hit it from 10 stories up.  (2.5 feet square is probably OK but anything smaller will probably not be hit.)
  3. Bring 3 pumpkins (each <8lb) to the Society of Physics Students lab (or to the Physics Shop) by October 21 (12:00 on Monday 10/24 at the VERY latest).  Note that we cannot guarantee that your specific pumpkins will be dropped on your catcher.
  4. Your pumpkin catcher needs to be able to be quickly (1 to 2 minutes) moved into position (by you) and quickly removed afterwards.
  5. Your team may consist of up to 4 people.
  6. No styrofoam peanuts.  They are too hard to clean up.
  7. Bring your pumpkin catcher to the lawn on the South side of BAL by 11:30 noon on Drop Day.
  8. You will get 1 extra credit point for building a pumpkin catcher (assuming a reasonable effort), 0.5 points for successfully catching a pumpkin without damaging it, and 0.5 points for answering the associated problems (see below).
  9. The College of Sciences will award two prizes for

a)      Shortest successful catcher,

b)      Most creative plausible catcher.

 Each prize is a $50 gift certificate to Barnes & Noble (shared equally by team members).

Pumpkin Problems:

  1. What is the force of gravity (in N) on your 9 pound pumpkin?
  2. What is its potential energy at the top of BAL (in J)?
  3. What is its kinetic energy the instant before it hits your pumpkin catcher (in J, neglect aerodynamic friction)?
  4. How much work does your pumpkin catcher have to do to stop it (in J)? [Hint: What is its kinetic energy after it has been stopped? How much did the catcher change the pumpkin's kinetic energy?]
  5. How tall is your pumpkin catcher (its height from bottom to top in m)?
  6. How much force does your pumpkin catcher exert on the pumpkin (assuming that it uses the entire height of your pumpkin catcher to decelerate the pumpkin)? [Hint: remember that Work Done = Force times Stopping Distance.]  Give your answer in Newton or in pounds.

Hints:  In the past, people have used empty milk jugs, water balloons, straw, etc.  Successful pumpkin catchers have ranged in height from 2 to 10 feet tall.


 
Last modified: Monday Oct 3, 2005