Initial Velocity from Highest point and angle?

AI Thread Summary
To determine the initial velocity of a projectile launched at an angle, knowing the maximum height and launch angle is crucial. The vertical speed can be calculated using the maximum height, as the projectile's speed is zero at that point due to constant vertical acceleration. With the vertical component of the initial velocity established, the horizontal component can be derived using the launch angle. Combining both components allows for the calculation of the total initial velocity magnitude. Understanding these relationships simplifies the problem of finding the launch speed.
litzkrieg
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Ok so having a little problem with this one and i feel like its easier than what i am seeing, but just not sure how i can get a V-initial from this (Replaced actual numbers with AAA and BBB because i am trying to recall how to do all this, hope ya'll don't mind variables to much lol)

The highest barrier that a projectile can clear is AAA m, when the projectile is launched at an angle of BBB ° above the horizontal. What is the projectile's launch speed



so i did use some trig and figured out the X-distance and the Hypot. but i wasn't given a time or acceleration...i've been looking through and rearranging some equations, and i feel like I am just missing something obvious...help please


Thank you, Litzkrieg
 
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If you know the projectile's maximum height, you can easily figure out its initial vertical speed, since the projectile experiences constant acceleration in the vertical direction, and its speed reaches 0 at max height.

If you know the vertical component of the initial velocity, and you know the angle, then you can find the horizontal component of the initial velocity.

Once you know both components, you can find the total magnitude of the velocity.
 
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