# Projectile Motion Kenimatics in Two Deminisions?

#### alexas

1. Homework Statement
Find the maximum height of a projectile that as the following velocity and is launched at that angle.
Intial Velocity: 4.736 m/s
Angle (in degrees): 40
Gravity: -9.8 ?

I was thinking....

{((-4.736m/s)^2)(sin(40))}/{(-2)(g)} but the hieght comes out extremely low...

I have a feeling i am using a wrong formula... Any ideas?

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#### LowlyPion

Homework Helper
Welcome to PF.

You really should be squaring the (sin40*Vo) but otherwise it won't go all that high will it, if the vertical component of Vo is about 1/3 of what gravity will knock down in 1 sec?

#### alexas

Sorry I meant to say the sin40 was also squared. Is the answer I get for thre sin^2 times v^2 divided by 2g the correct one?

#### LowlyPion

Homework Helper
Sorry I meant to say the sin40 was also squared. Is the answer I get for thre sin^2 times v^2 divided by 2g the correct one?
Looks ok to me.

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