Question

what type of energy increases when heat is added to a substance? potential energy increases. energy does not increase. kinetic energy increases.

Explanation:

When heat is added to a substance, the temperature of the substance generally increases (except during phase - change). Temperature is a measure of the average kinetic energy of the particles in a substance. As the temperature increases, the average speed of the particles (atoms/molecules) increases. Since kinetic energy \(K = \frac{1}{2}mv^{2}\) (where \(m\) is the mass of the particle and \(v\) is its velocity), an increase in the speed of the particles means an increase in kinetic energy.

Potential energy is related to the position or state of the particles (e.g., in a phase - change, potential energy changes while temperature remains constant). But in a general case of heating (without a phase - change), potential energy does not change significantly. And energy does increase because heat is a form of energy transfer.

Answer:

Kinetic energy increases.