- #1

jmwachtel

- 35

- 0

## Homework Statement

A 20.0 kg cannonball is fired from a cannon with a muzzle speed of 1050 m/s at an angle of 42.0° with the horizontal. A second ball is fired at an angle of 90.0°.

(a) Use the isolated system model to find the maximum height reached by each ball.

(b) What is the total mechanical energy of the ball-Earth system at the maximum height for each ball? Let y = 0 at the cannon.

## Homework Equations

Ei = Ef

K = (1/2)mv^2

U = mgy

## The Attempt at a Solution

I know that you can solve for h by setting these two equal, but I don't understand why that works. I need to understand how these relate. I have no idea what to do for b. Thank You.