Is this the right equation to use?

[magnifik]

Homework Statement

A cannon ball is fired with speed v0 at an angle phi above the horizontal. The launch point is at height h above the ground. Find the time to hit the ground, and the magnitude of the velocity when the ball hits the ground (in terms of v0, g, h, $$\phi$$)

Homework Equations

y=v0sin($$\phi$$)t - 1/2gt^2
vy=v0sin($$\phi$$) - gt

The Attempt at a Solution

how do i account for initial height?

 

[rock.freak667]

Homework Equations

y=v0sin($$\phi$$)t - 1/2gt^2
vy=v0sin($$\phi$$) - gt

The Attempt at a Solution

how do i account for initial height?

y=y₀+v₀sin(φ)t - 1/2gt²