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Temperature
Beginner
A measure of the average kinetic energy of particles.
Temperature measures how hot something is: the average translational kinetic energy per particle, and the property that decides which way heat flows. Two bodies in contact exchange heat until their temperatures match.
Room temperature air has molecules averaging about 500 m/s.
Temperature isn't heat; a bathtub of warm water holds more heat than a boiling cup.
In more detail
Temperature measures how hot or cold something is, and at the particle level it relates to the average kinetic energy of the molecules. Two objects in contact tend to reach the same temperature.
Real-world uses
- Weather forecasts report air temperature to plan clothing and heating.
- Industrial furnaces are controlled by precise temperature measurements.
- A weather app shows air temperature, which reflects how fast the air molecules are moving on average.
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Frequently asked questions
Is temperature the same as heat?
No. Temperature describes how hot something is, while heat is energy transferred because of a temperature difference.
What is absolute zero?
The lowest possible temperature, 0 K or about −273.15 degrees Celsius, where molecular motion is minimal.
Is temperature a measure of heat?
No. Temperature tells you the average energy per particle, while heat is the energy transferred because of a temperature difference.