Is potential energy a form of energy that is stored in a object before it moves?
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Potential energy is a mathematical concept. When we say that something has potential energy then it does not have this energy yet. For example, once something falls it can gain kinetic energy due to gravity, so before this conversion it was only potential energy, and it did not have this in form of kinetic energy. It is something that helps with calculations. Potential energy is not (yet) actual energy, as far as we can call energy “actual”. It is also a concept. You could ask “Is energy real”? And there would be opinions.
At a high level, you could consider potential energy to be stored energy, but it’s perhaps more helpful to go back to why we have the concept of energy.
Energy is basically the extension of the idea that (for example) if for example you run and hit a box, then you will slow down and the box will go flying. In this case, you have (kinetic) energy, then it gets transferred into the box.
Another example is if you throw something heavy into the air, it will slow down, then speed up again and fall back down. Notably, by the time it finishes falling down, its downward speed will be the same as the original upward speed when you threw it.
In both cases, we have the idea that the total energy is “conserved” (i.e. unchanged) throughout the process. In other words, energy is a useful mathematical concept of some “ability to do work” which is *conserved* throughout the process.
Now, what is potential energy? If you consider the throwing example, the object slows down in the air so it loses kinetic energy (temporarily). The energy which is “temporarily gone” we call potential energy, so that the potential plus kinetic energy together is “conserved”.
At this point, you might say, “isn’t that cheating? How can you just call the missing energy potential energy and say it’s still conserved?” Well, it’s because there’s a nice separate formula (m * g * h) to calculate the potential energy due to gravity, so it is actually meaningful to say that the kinetic energy plus the potential energy (by this formula) is conserved. (Or said another way, we can specifically account for the missing kinetic energy as “it slowed down due to gravity in this mathematically precise way”.)
It’s more like the energy that it can potentially gain. Unless it’s an accumulator. Then it’s the stored energy
Potential energy is how far from equilibrium something is. When you stretch a rubber band, you’re adding potential energy. If you let go, it can turn that potential energy back into kinetic energy as it returns to rest.
The same is true for boulders on hills, big molecules that have been built up and could fall back apart to release energy, etc.
You know the idea that someday the universe will die a ‘heat death’ and everything will be perfectly evenly distributed? Potential energy is in everything that hasn’t yet collapsed to that state.
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