Finding the Total mechanical energy

AI Thread Summary
The discussion focuses on calculating the total mechanical energy of a shot put as it is released and reaches its maximum height. The potential energy at release is determined using the height and mass, while the kinetic energy is calculated from its speed. The total mechanical energy at release combines both potential and kinetic energy. At maximum height, the potential energy is at its peak, and the kinetic energy is zero, leading to a total mechanical energy that remains constant. The participant successfully identifies the total mechanical energy at maximum height as 661 J by summing the potential and kinetic energies.
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At the moment when a shot putter releases a 5.00 kg shot, the shot is 2.00 m above the ground and traveling at 15.0 m/s. It reaches a maximum height of 8.00 m above the ground and then falls to the ground. Assume that air resistance is negligible.

a. What was the potential energy of the shot as it left the hand, relative to the ground?
b. What was the kinetic energy of the shot as it left the hand?
c. What was the total mechanical energy of the shot as it left the hand?
d. What was the total mechanical energy of the shot as it reached its maximum height?
e. What was the potential energy of the shot at its maximum height?
f. What was the kinetic energy of the shot at its maximum height?
g. What was the kinetic energy of the shot just as it struck the ground?

I've got the answers up until question c). But I've been stuck on d) I know the answer is 661 J but I don't know how








The Attempt at a Solution

 
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sum answers e and f to get d
 
Thanks got it!
 
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