Projectile Motion comparing height and initial velocity


by DarkBlitz
Tags: comparing, height, initial, motion, projectile, velocity
DarkBlitz
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#1
Jan12-12, 11:19 AM
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
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#2
Jan12-12, 11:28 AM
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Quote Quote by DarkBlitz View Post
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.
DarkBlitz
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#3
Jan12-12, 12:37 PM
P: 20
I got an answer or root(2), is this correct?

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Jan12-12, 12:50 PM
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Projectile Motion comparing height and initial velocity


Quote Quote by DarkBlitz View Post
I got an answer or root(2), is this correct?
Yes.
DarkBlitz
DarkBlitz is offline
#5
Jan12-12, 12:51 PM
P: 20
Thank you very much!


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