# Projectile Motion

I know the angle at which a projectile is launched, how far it needs to go, and also the maximum height. How can I find the initial velocity needed (disregarding air resistance)?

Currently, I am using:

$Vf^2=Vy^2-2g\Delta y$

From that, I can find the velocity in the y direction needed for the projectile to reach the known maximum height.

Next, I am finding the time it takes to reach that maximum height by using the found y velocity.

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 There are loads of articles out in Googleland on calculating the trajectory of a projectile, and indeed searching this site for "projectile" finds lots of related questions. – John Rennie Sep 18 '12 at 11:30 – John Rennie Sep 18 '12 at 11:32