How do you make a simple rocket?

Question

It has to travel at least 1.5 meters.

Answer 1

Inflate a balloon and release it without tying it off. The long skinny ones go pretty straight.

Answer 2

Anything that will push a force out of the back end with sufficient energy to offset the weight and drag of the anything will demonstrate the characteristics of a rocket. The previous answers are specific and correct. I've done both when I was a kid. [I don't recall the match answer, but when you wrap tin foil around the rocket match do so with a pin aligned along its longitudinal axis and sticking out at the back away from the match head. Once you have wrapped the match, pull the pin out...the resulting hole at the back of the tin foil will be your nozzle hole. Be careful with this one; it travels fast and without aim.]

Here's the equation you'll be working with to get your rocket moving. f = ma = T - D - W sin(theta); where f is the net force acting on your (match or balloon) of mass m, T is the force of the burn or air spewing out (thrust), D ~ 0 is the drag of the air on your match or balloon, W is the weight of either one (including the air inside for the balloon), and theta is your launch angle wrt the ground.

Generally speaking, the drag will be negligible because your rocket won't be going fast enough. Drag depends on the velocity of the rocket as well as other factors. But the weight of your projectile will be a significant factor.

For example, you have to balance the weigtht issue with the strength issue for the match rocket. Too much tin foil and it will weigh too much to go far, if at all. Too little and the match will explode (not very much) and there will be no thrust out the back.

Answer 3

wrap a paper match in tinfoil and hold another match under it to light it. Angle the rocket at 45 degrees for maximum range.