Conservation of Energy with heat

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jakeginobi

Homework Statement


A 45 kg steel ball is projected vertically with an initial speed of 280 m s . While the ball is rising, 8.5E5 J of heat energy are produced due to air friction. What is the maximum height
reached by the ball?

Homework Equations


Ek = 1/2mv^2 Ep = mgh

The Attempt at a Solution


I started with Ekbefore=Epafter+Ekafter-Eheat
so It'll be 1/2(45kg)(280m/s) = (45kg)(9.8m/s^2)h + 1/2(45kg)(0) - 8.5E5 J
Solving for H, I got 5927.44 m, the answer is 2100m (rounded), am I suppose to add the heat energy or subtract it from the energy after?
 
on Phys.org
Chestermiller said:
What do you get if you add it? This should give you your answer.
So I'm suppose to add the heat energy to the energy after?
 
Chestermiller said:
Yes. Why do you think that this is so?
It's because of conservation of energy? The energy before = the energy after