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## Homework Statement

The longest homerun hit by Miguel Cabrera in the 2012 season occurred at Comerica Park and had an initial y-component of velocity of 19.8 m/s and an initial x-component of velocity given as m/s, where is some value left undetermined.

Assume the ball left the bat 1.22 m off of the ground. (Ignore the effects of air resistance.) Give the following:

a) the initial kinetic energy

b) the initial gravitational potential energy

c) the kinetic energy at the maximum height

d) the gravitational potential energy at the maximum height

e) the maximum height above the ground (you must find this using energy calculations)

## Homework Equations

a) KI= 1/2 m1v1^2+ 1/2 m2v2^2

b) GPE= mgh

c)When the ball is at maximum height the velocity is 0 therefore i think the kinetic energy is also 0?

d) When the ball is at maximum height the velocity is 0 therefore i think the gravitational potential energy is 0..?

e)hmax=v^2(sin^2(θ))/2g

## The Attempt at a Solution

a)KI=(1/2 m1(19.8m/s)^2) + (1/2 m2 (v m/s)^2)

=9.9m^2/s^2 (m1) +(m2 v m^2/s^2)/2

I feel like I am just missing a lot of information and don't understand how to find the mass of the ball..

b)GPE initial= mgh

(m)(9.8 m/s^2)(1.22m)

Once again i don't have mass so I'm confused where to go from here

c) 0

d) 0

e) i don't know if the formula I've shown is using energy calculations or not, and if it is i don't understand how to find θ and what velocity to use.