# Projectile Motion comparing height and initial velocity

by DarkBlitz
Tags: comparing, height, initial, motion, projectile, velocity
 P: 20 Hey, I came across this question in my text book, and there isnt an answer for it in the back, so I would just like to check if I have my head around it. The question is: 2 projectiles are launched at the same angle. Projectile 1 reaches a max height of twice that of the projectile 2. What is the ration of the initial speeds? I said that they where in the ratio 4:1, as one of the formulas is: y=yo +voyt -0.5gt^2 and because the height is doubled, the time taken must also be doubled? am I correct in saying this? Thanks
Mentor
P: 40,238
 Quote by DarkBlitz I said that they where in the ratio 4:1, as one of the formulas is: y=yo +voyt -0.5gt^2 and because the height is doubled, the time taken must also be doubled? am I correct in saying this?
No.

Come up with a formula that relates max height with initial velocity without the need for the time.
 P: 20 I got an answer or root(2), is this correct?
Mentor
P: 40,238

## Projectile Motion comparing height and initial velocity

 Quote by DarkBlitz I got an answer or root(2), is this correct?
Yes.
 P: 20 Thank you very much!

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