ashf1mclaren wrote:hi i am taking part in the f1 in schools championship, i was wondering how much energy is stored in the co2 cartridges (8 gram) we use as propulsion
Tape it down to a pair of scales, pull the pin and see the force.
Although you might want to be a bit more scientific than that. See if your school has any accurate newton meters that can be hooked up to datalogging software, with a short sample period (so lots of samples whilst the cartridge fires). Get some thrust profiles (ie a graph of x=time(s) y=thrust(N)), maybe even post one here so we can see what it looks like.
Then the total impulse would be the total area under the graph (or the integral of the line, if you want to get all mathsy).
And the total energy in that would be.... oh dear god, I can't remember. A curse upon big lunches. I'm sure your physics teacher would know, hell it's probably so simple my cat would know.
But I doubt the total energy would be very helpful to know- the physics of the project is going to be all about impulses and thrust profiles. If you get it to work, post what ya get here, it'd be interesting.