Thermal energy

Definition

Thermal energy is the internal energy of a system due to its temperature. It arises from the random motions of atoms and molecules within the system.

5 Must Know Facts For Your Next Test

1. Thermal energy is a form of kinetic energy resulting from the motion of particles in a substance.
2. The amount of thermal energy depends on both the temperature and the mass of the system.
3. Heat transfer occurs when there is a difference in temperature between two systems, resulting in thermal energy flowing from hotter to cooler regions.
4. In thermodynamics, thermal energy is often measured in joules (J) or calories (cal).
5. The concept of thermal equilibrium refers to two systems reaching the same temperature and thus no longer exchanging thermal energy.

Review Questions

• What factors determine the amount of thermal energy in a system?
• How does heat transfer relate to thermal energy?
• What units are commonly used to measure thermal energy?

Related terms

Kinetic Energy:

The energy possessed by an object due to its motion, given by $\frac{1}{2}mv^2$ where $m$ is mass and $v$ is velocity.

Conservation of Energy:

A fundamental principle stating that total energy in an isolated system remains constant over time.

Temperature:

A measure of the average kinetic energy of particles in a substance, often measured in degrees Celsius (°C), Kelvin (K), or Fahrenheit (°F).