What is defined as energy in action?

Kinetic energy is defined as energy in action. This form of energy is associated with the motion of objects; any object that is in motion has kinetic energy. For example, a moving car or flowing water is exhibiting kinetic energy because they are in motion and thus have the capacity to perform work or cause changes in the environment around them.

In contrast to kinetic energy, potential energy is stored energy that has the potential to do work but is not currently in action. This is like a rock held at the top of a hill, where it has the potential energy due to its position but is not actively moving.

Chemical energy is a type of potential energy that is stored in the bonds of chemical compounds, like molecules of food. While it can be released and transformed into kinetic energy through chemical reactions, it does not represent energy in motion until it undergoes such a transformation.

Mechanical energy is the sum of kinetic and potential energies in a system. While it encompasses both types of energy, it is not solely defined as energy in action, as it includes energy that is stored as well.

Thus, the correct identification of kinetic energy as energy in action reflects its definition within the context of physics and allows for a clear understanding of how energy operates in various forms.