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Homework Statement
Find the kinetic energy lost
Homework Equations
The Attempt at a Solution
We solved it in class
Ek1 = -206 J
Ek2 = 10 J
Find the energy lost.
The answer is was 2.2 * 10^2 J lost
This is confusing for me, to find energy lost, we should subtract the initial energy from the final energy, or should we subtract the final from the initial? So is the answer
Ek1 - Ek2 = -206 J - 10 J = -216 J
or
Ek2 - Ek1 = 10 J - (-206 J) = 216 J
How do we do it?
I know for example if someone has say 10 marbles, and loses 3, we have seven left. So the amount lost should be
10 - 7 = 3
Or initial - final.
Or is it final - initial = 7 - 10 = -3 ?