# Need Source of Projectile in Vacuum Outcome

https://www.physicsforums.com/showthread.php?t=75116 (the url has spaces) it said "shooting the projectile at 45 degrees will yield the greatest distance..." Where do you find that information. I need to know for my scientific experiment for school. I know this fact is true, but where is the source of this information? Thnx in advance.

Sorry if I post this is the wrong section. I really don't know where this thread should go Last edited by a moderator:

## Answers and Replies

Hootenanny
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Science Advisor
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http ://ww w.physicsforums.com/showthread.php?t=75116 (the url has spaces) it said "shooting the projectile at 45 degrees will yield the greatest distance..." Where do you find that information. I need to know for my scientific experiment for school. I know this fact is true, but where is the source of this information? Thnx in advance.

Sorry if I post this is the wrong section. I really don't know where this thread should go One can derive a set of kinematic equation (for constant acceleration) using Newton's second law. The equations of most interest are,

$$s = v_0t+\frac{1}{2}at^2$$

And the defintion of speed,

$$v = \frac{d}{t} \Rightarrow t = \frac{d}{v}$$

One then needs to consider motion in the vertical and horizontal directions separately. For more information you can try Googling for Projectile Motion.