I know the definition of energy mathematically and how to work simple physics problems using energy considerations.However, I'm trying to look at energy from an intuitive standpoint.So far, this is what I have...Energy is essentially the ability to make things move.Saying that something has energy is saying that it possesses some trait or characteristic that gives it the ability to alter the physical condition of something else. So saying that something has kinetic energy is saying is just saying that because this object is moving, it has the ability to make other objects move.But I'm not sure if this intuitive definition directly translates to the formal definition of the capacity to do work.If energy is the ability to be a force acting through some displacement then when a moving billiard ball collides with a stationary ball and makes it move is it correct to say that the moving ball did work on the stationary ball to get it to move?Since energy is transferred from the moving ball to the stationary ball work must have been done on the stationary ball right?The part where I'm confused is all the examples of work and energy transfers in my textbook involve some constant force pushing or pulling on something over a distance and all the examples that involve the transfer of motion by collision deal with momentum and not work?But that moving ball colliding with the stationary ball is a force which is doing work on the stationary ball right?so why is only momentum talked about for these examples and not energy?(adsbygoogle = window.adsbygoogle || []).push({});

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# I'm having trouble understanding exactly what energy is.

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