Which object has less thermal energy?
a 300-gram glass of water at a temperature of 75°F a 300-gram glass of water at a temperature of 80°F
The objects are identical except for their temperatures.
All solids, liquids, and gases are made of matter. Matter is made up of tiny particles that are always moving. The energy from the motion of these particles is called thermal energy.
Temperature measures how hot or cold matter is. If the particles in matter slow down, the temperature goes down. The matter now has both less thermal energy and a lower temperature.
The two glasses of water have the same mass but different temperatures. Since the 75°F glass of water is colder than the 80°F glass of water, it has less thermal energy.