Ok, race fans. I've completed some initial testing. The first run couldn't
have been more dissappointing. I carved a pickup bed style spot for the
cartridge and taped it in place. I also taped the body of a bic pen
underneath with string running through it to have some control over the
trajectory. In the first test, the hole was too small, and the cartridge
just hissed at me mockingly with no motion. After overcoming the initial
dejection, I lightened the car and tried again with the intent to make a
bigger hole. Before I knew it, it was over. The acceleration is impossible
to see for the first foot. I think I have found my winner. I think this is
a fantastic demonstration of Newton's second law. For anyone worried about
safety, I figure getting hit at the peak of motion would be similar to being
hit by an 8 year old. The only problem I have to work out is how to make
sure I can start it at the very second I need it to. So far, I have taped a
nail to the end, and struck the nail with a hammer. This works great, but
requires quite a bit of coordination for it to work well, and the nail ends
up being kicked backward with little energy (which is not a safety hazard,
unless you place your eye directly behind the rocket). I have 14 days to
figure out how to develope a starting scheme. I declare this project as
"too much fun not to try". It is very simple and cheap. The pinewood derby
car kit was $3 from the boy scouts, and the cartridges are 5 for $3 at
walmart. I have some ideas for the start. I'll give an update when I have
it figured out, and I'll try to get some numbers for distance/time. Thanks
to everyone for your comments, they are very appreciated.