Like, i know it’s the ability to do work and all that, but this isn’t what energy is, it’s what energy does. What IS energy tho?
In: Physics
>What IS energy tho?
In some cases, the only way to see, in the physical world, how much energy something has, is to measure how far away it is from other objects.
For example, we talk about [gravitational potential energy](https://en.wikipedia.org/wiki/Gravitational_energy); two bodies have gravitational potential energy if they are far apart.
* A mass of water has gravitational potential energy because of how the force of gravity is trying to pull it towards the center of the earth’s mass.
* The farther it is from the center of mass, the more energy it has; and we can use this energy to do work; that’s how a [water wheel](https://en.wikipedia.org/wiki/Water_wheel), or a hydroelectric plant.
But gravity isn’t the only force of attraction. Electromagnetic attraction is possible too. In fact, electromagnetic attraction is the force that governs chemical reactions, and all the chemical bonds that hold objects together. So what does an electromagnetic version of potential energy look like?
A rubber band has what we call [elastic energy](https://en.wikipedia.org/wiki/Elastic_energy). We can think of elastic energy as a form of distance too: it exists when we stretch the ends of the rubber band a farther distance from one another, than they would ordinarily be.
Ultimately, elastic energy exists because of elasticity, a property where the particles that make up an object try to return themselves into a certain shape. When we stretch those particles out of shape, the energy is embedded in the distances of how far away they each are from their ideal position.
So we could say that energy is the potential for one of the fundamental forces of nature, to move an object across a distance. This fits with how, mathematically, energy is force times distance.
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