Gun Powder

How much gun powder should be used to launch a firework 50 feet in the air?

And no, I’m not planning on making an actual firework.
OK, it’s a school project, all I know is that it has to go up 50 feet and the powder it KNO3 + S + C

If you aren’t going to make it, then why do you care? Sorry, that must be the programmer in me asking a logic statement. NM. Anyways,

You didn’t mention the mass or shape of the projectile. The weight of the object is a MAJOR consideration so assuming you are launching on Earth, the mass must be known because Earth gravity is a constant and the mass will give us weight (you could also just weigh the thing, if you are on earth now). The shape of the object must be known because Earth atmosphere has a specific composition and therefore a specific known and constant drag coefficient given your specified launch altitude and knowing the relative humidity at launch, of course. The complex physics involved in determining altitude given a certain variable force must take into account the shape of the object in order to compute drag upon same.

You also didn’t mention what exactly your “gunpowder” (as if there were only 1 known compound listed under that common nym) is composed of. That must also be a known constant.

Can you be more specific, please? If you can, I will give you your figure.

Thank you!

Home Brewed Gun Powder – Lesson in Safety