How to do calculations for a cannon distance, angle, etc?

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aj23
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Mon Jun 04, 2012 4:55 pm

I know there are programs out there for the calculations, but I need the actual data and each step in the calculations for a physics project. Does anyone know how this would work with a pneumatic cannon using a piston valve, in terms of figuring out the distance it can fire with given angles and pressure?
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Technician1002
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Mon Jun 04, 2012 5:12 pm

This is complex. Too many variables are unknown. On earth, air atmosphere provides randomness to projectiles with undefined aerodynamics. I would not even want to calculate the landing area of this example shot below. As you can see the atmosphere has a huge impact on the flight of the projectile.
http://www.youtube.com/watch?v=y2fDxDCHPfo
The projectile flight is not predictable without a complex fluid dynamics model.

If your projectile has a more ballistic flight path, then a ballistics prediction can be made using known launch angles and velocity. Try using GGDT.
http://www.thehalls-in-bfe.com/GGDT/usa ... istic.html
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jackssmirkingrevenge
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Tue Jun 05, 2012 12:49 am

http://hyperphysics.phy-astr.gsu.edu/hbase/traj.html

It gets a little more complex when you throw in air resistance though.

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hectmarr wrote:You have to make many weapons, because this field is long and short life
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D_Hall
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Tue Jun 05, 2012 8:52 am

Alternatively, in recent days some Indian-born kid in Germany supposedly came up with a general form equation to answer ye ol' ballistics problem. A bit of research to see what the kid did could prove to the teach that you can do it and that you're up on current events in science.
Simulation geek (GGDT / HGDT) and designer of Vera.
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Tipsypyro
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Mon Jan 19, 2015 11:56 pm

Cant find it. Do you have a link?
As within, so without. As above, so below.
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