I have been working with projectile motion, and I am just starting to add air friction (drag) into the equations. I've run into a bit of a wall in terms of the calculations, so any help would be appriciated.(adsbygoogle = window.adsbygoogle || []).push({});

For a projectile, F(drag)=-c.V^2, where c is a constant (which can be written in terms of cross-sectional area, etc.)

Therefore: Acc(drag)=-c.V^2/(mass)

When I write an expression for vertical velocity [V(t)] at a given time [t], I get:

V(t) = V(initial) - 9.8t - (c/m). INTEGRAL{ [V(t)]^2 }dt

I then look at this equation and have trouble writting V(t) without an integral (or derivative for that matter).

I showed the problem to a friend, who gave me a strange tangent function for V(t), which I can't quite get my head around, as there is no mention of angles at this stage.

Maybe I'm on the wrong track, or maybe my calculus skills aren't quite up to scratch. Eventually I want to create a model for the projectile's motion (in terms of x and y), but first I need to get this part right.

Thanks for any help.

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# Homework Help: Projectile motion including drag

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