Question

Which best describes thermal energy?

a) It is the difference between internal energies of two or more substances.
b) It is the sum of internal energies of two or more substances.
c) It is the portion of internal energy that can be transferred from one substance to another.
d) It is the portion of potential energy that can be transferred from one substance to another.

Answer 1

Thermal energy is the average kinetic energy of particles in a substance and is a subcategory of internal energy. When two objects at different temperatures are brought into contact, the transfer of thermal energy between them is heat.

Step-by-step explanation:

Thermal energy is the average kinetic energy of the particles (molecules or atoms) in a substance. It is one of the subcategories of internal energy, which is the sum of the kinetic and potential energies of the atoms and molecules in a system.

For example, when two objects at different temperatures are brought into contact with each other, energy is transferred from the hotter object to the colder object until they reach thermal equilibrium (i.e., they have the same temperature). This transfer of energy is heat.