Hi! I've written a simple software to calculate projectile trajectories when air resistane can't be neglected. I'm planning to test the software with a light ball and a cannon.(adsbygoogle = window.adsbygoogle || []).push({});

My model simply say

F = -k * A * v^2

The force of drag F is proportional to the velocity v squared. k and A are constant of drag and frontal area respectively.

Can anyone tell me what the constant k would be for a sphere?

The ball I'm planning to use is about 2.5 cm in diameter, weighs about 5 g (guess) and is pretty smooth. It will be launched at speeds of about 5 - 7 m/s.

If the information is insufficient, please ask.

Edit: Please use SI units, thanks!

//Sigma

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# Aerodynamics of a ball

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