The study of energy and its changing form is called

The study of energy and its changing form is called thermodynamics. Thermodynamics is the branch of physical science that is concerned with conversions between heat and other forms of energy such as chemical, electrical or mechanical energy. Under thermodynamics, energy can be transferred from one place to another and from one form to another.

there are so many examples for that in different areas, like biology experiment carried out in our lab recently.

here's one link: