So, being the uneducated schmuck that I am, I've gotten stuck on this (part of an) assignment that I have, due for tomorrow.
Basically, it reads (translated):
"Prove that a change of potential energy is a work. Basically you should show that a change in potential energy equals force times distance."
Yeah, it's weirdly worded, but it's not much better in Swedish (I believe the teacher is dyslexic).
Anyone who can give me a hand?