- #1
fog37
- 1,568
- 108
Hello Forum,
I understand that energy, either kinetic is a relative quantity whose value depends on the frame of reference and its motion. Is that true for potential energy as well?
I read on a physics book that only changes in energy can be measure. What does that exactly mean? Why can we not measure energy directly but only its changes? Energy is apparently the measure of change of a system. What matters are energy differences and energy changes. Is it not correct to state that a system has a certain amount of energy at a particular time? Should we only talk about energy gains and energy losses for a system?
Thanks!
I understand that energy, either kinetic is a relative quantity whose value depends on the frame of reference and its motion. Is that true for potential energy as well?
I read on a physics book that only changes in energy can be measure. What does that exactly mean? Why can we not measure energy directly but only its changes? Energy is apparently the measure of change of a system. What matters are energy differences and energy changes. Is it not correct to state that a system has a certain amount of energy at a particular time? Should we only talk about energy gains and energy losses for a system?
Thanks!
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