It increases. It decreases. It remains constant. It is transferred out of the system.
I gave my students this multiple choice question: In a closed system, what happens to the total energy of the system as energy conversions take place?

Only one answer is correct among these 4 choices:
- It increases.
- It decreases.
- It remains constant.
- It is transferred out of the system.

Could you tell me which one is correct?

It remains constant.