Projectile Mathematics

[Arthur]

Is anyone good with the mathemetics of projectile flight? Is there a way of calculating height achieved by a firework shell, even a method from artillery ranging?

[Skycastlefish]

I have a book called Backyard Ballistics by William Gurstelle and it has a very practical method of estimating altitude. Here's a link -- click on "look inside" go to page 43. The protractor is pretty fun and you can modify it to make it sturdier.

http://www.flipkart.com/backyard-ballistic...35d#previewbook

Edited December 31, 2009 by Skycastlefish

[TheEskimo]

I would have to suggest skycastlefish's method. With a shell, you can't guess it's velocity unless having some good equipment, or allowing it to fall to the ground. Using the protractor will give a much better measurement than fiddling around with time, and wind resistance.

Just find your angle when the shell explodes, and apply the tangent formula to it. Tangent(x)=opposite/adjacent. Adjacent is your distance from the mortar. X is the angle gained from the protractor. Opposite is the height of the shell, once gained from completing the formula. Just like geometry class way back in high school.

Example: Tan(75)=opp./100ft-->tan(75)*100ft=opp.-->373ft=opp.--> The shell got to 373 feet.

Xetap's method, while useful, is best used for "perfect" lab conditions i.e. no wind, friction, perfect readings, etc. Whereas using the protractor, you lose many variables, and your readings will be much more accurate.

And using the salute method will include even more math, having to determine the hypotenuse(the distance the sound travels), and knowing the adjacent side (distance from mortar), and putting this into Csq-Bsq=Asq. And with having to round more, and be perfect with timing the salute, this method will be very inaccurate

Unless Mumbles the Big-Brained has a better method, I would say go with the protractor method.