Heat
What happens when you touch a cup of hot tea? You hand gets warmer. Heat flows from the cup to your hand.
What happens when you hold a glass of ice water? You hand gets cooler. Heat flows from your hand to the glass.
Heat flows from hotter to colder bodies. The hotter body is said to have a higher temperature. The colder one is said to have lower temperature.
In physics, the term "heat" refers to the energy that is transferred from one body to another.
If a body is hotter, it obviously has more energy than a colder one. However, we do not say that the hotter body has more heat energy. Instead, we say that it has more "internal energy," or "thermal energy."
When a hotter body is in contact with a colder one, thermal energy is
transferred from one to the other. The exact amount that is transferred
is called "heat."
Copyright 2010 by Kai Hock. All rights reserved.
Last updated: 11 October 2010.