Projectile Motion without Initial Velocity

[PerryKid]

Projectile Motion without Initial Velocity (Only time and angle given)

Homework Statement

A projectile is launched at an angle of 50° above the horizontal and it hits the ground in 12 seconds.

a. Calculate the maximum height of the projectile.
b. Find the range of the projectile.

Homework Equations

H_{max}=\frac{V_{o}^{2}+sin^{2}\theta}{g}

R=V_{o}\sqrt{\frac{2H}{g}}

The Attempt at a Solution

I don't know where to start. I can't solve without V_o and I am missing V_o.

 

[lewando]

Can you not use a standard kinematic equation to get v_y0?

 

[PerryKid]

I need [STRIKE]Vo to find height and range, not Vyo[/STRIKE]

EDIT: I found a formula to help me solve it all!

V_{y}=V_{o}Sin(\theta)-gt

V_{y}=0

 

[lewando]

But if you can find v_y0, then you can find v₀ with some simple trig.

 

[lewando]

EDIT: I found a formula to help me solve it all!

V_{y}=V_{o}Sin(\theta)-gt

V_{y}=0

That will work. At what t will v_y = 0?