Quote:
Originally Posted by Xist
Oh boy. I was just thinking that if I made a track five times as long, on a ramp, I could get a 65 MPH pinewood derby car, but it would not be scientific.
Just fun.
Like Mythbusters! 
What if you laid a hundred feet of PVC pipe on a good hill, wide enough for the car to roll, sealed as long as you can measure the final speed before it hits a bean bag of bag's worth of cotton balls.
What kind of pressure would you need? |
You'd have to build a road on the floor of the pipe to create the test section,and size the pipe such that the model was no more than 5% of the test section cross-sectional area.
And you have to know the rolling resistance for the tires/wheels beforehand.
As to the pressure,you'd want to talk to NASA or an organization like that.