Sorry, my English is poor haha. Teacher suggests using the wood to make the catapult. 'Respectively' I mean is need to launch the ping pong ball twice. First distance is 4m and second distance is 10m. I think I am not going to use the gun powder and explosive propellant.
1. The shape of the ping pong launcher I think is 'catapult' but I don't know the suitable size and the materials need to use. The ping pong ball need to be launch to a distance of 4m and 10m respectively.
What are the size and materials used is most suitable to launch the ping pong ball this far ?