(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A ball of mass 240 g is moving through the air at 20.0m/s with a gravitational potential energy of 70J. With what speed will the ball hit the ground?

2. Relevant equations

Eg = mgh

Ek = 1/2mv^2

W = mgd

3. The attempt at a solution

this is what i did:

at 0m, potential energy is 0 so kinetic energy must have 70J now.

Ek = 1/2mv^2

70 J = 1/2(0.24kg)v^2

v = 24.15 m/s

I dont know what to do with the 20 m/s that was given and yeah....please help!

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# Homework Help: Conservation of mechanical energy of ball of mass

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