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## Homework Statement

A man stands on the roof of a building of height 14.1 m and throws a rock with a velocity of magnitude 31.6 m/s at an angle of 25.0 above the horizontal. You can ignore air resistance.

Calculate the maximum height above the roof reached by the rock.

Calculate the magnitude of the velocity of the rock just before it strikes the ground.

Calculate the horizontal distance from the base of the building to the point where the rock strikes the ground.

## Homework Equations

V^2 = V initial ^2 + 2a(x-xo)

## The Attempt at a Solution

The first part is the part, that I am getting stuck on, the other two parts of the question following it hopefully I will be able to do, as I encountered that type of problem before.

Anyways, my attempt:

Max height = unknown

Angle : 25 degrees

Vy = 0 m/s (at the highest point, Velocity is 0.

Vy initial is 13.35 m/s. ( I got this using 31.6 sin 25)

Height at beginning is 0. (Ignoring the fact that's the building is 14.1m)

0 = 13.35^2 + 2 (-9/8)(y-0)

-178.22 = -19.6y

y = 9.09 m

does this seem right?

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