What Is Thermal Energy?

Thermal energy is the result of the movement of particles called molecules and atoms. This energy can be transferred from one object to another due to the difference in temperature.

What is thermal energy?

When we touch any material that conducts heat if it has a temperature higher than that of our body we feel warm. We are transferring thermal energy from our bodies to this material.

The unit of thermal energy in the IS is Joules (J).

What Is the Definition of Thermal Energy?

Thermal energy definition is the manifestation of energy in the form of heat. In all materials, the atoms that make up their molecules are in continuous movement, either moving or vibrating. It is also called thermal energy.

Moving particles implies that the atoms and molecules have a certain kinetic energy. Internal energy is the energy of these particles. Therefore, thermal energy is the internal energy of a body. If kinetic energy increases the particles move faster and get higher temperatures.

The internal energy of a thermodynamic system can be changed in two ways: by doing work on the system and by exchanging heat with the environment.

Heat Energy Examples

This type of energy is often linked to other types of heat energy. Here are some examples of thermal energy:

  • Nuclear energy. In the process of nuclear fission, a large amount of heat energy is released.

  • Chemical energy; chemical reactions may absorb or generate heat.

  • Geothermal energy uses heat from the interior of the Earth.

  • Fossil fuels used in the combustion of fossil fuels (for instance, heat engines).

  • Heating systems use convection heat transfer in order to get warm air. Since the air is a fluid, differences in temperature favor convection; hot air rises and cold air down. The more movement, the more heat exchange with the surrounding air.

How Is Heat Energy Transferred?

The word heat is used to describe the energy in transfer to or from a thermodynamic system.

This form of energy can be transmitted from one body to another following the laws of thermodynamics in three different ways: radiation, conduction, and convection.

  • Radiation heat transfer; energy is transmitted through electromagnetic radiation (electromagnetic waves).

  • Thermal conduction is the transfer of heat from a hot body is in physical contact with a cooler body. The materials that can do it easily are called conductors of heat.

  • Convection heat transfer occurs when hot molecules are moved from one side to the other. This method of heat transfer would be the case of the wind, capable of moving molecules with certain thermal energy.

What is thermal energy?

Infrared radiation is invisible to the human eyes, but we can sense it as heat. These waves occur at frequencies above those of microwaves and just below those of red visible light.

Convection and conduction are the two most prominent methods of heat transfer in liquids and gases. Molecules in a gas or liquid in contact with a solid body transmit or absorb heat to or from that body and then move away.


    Published: December 10, 2009
    Last review: May 16, 2020