What happens to the temperature when kinetic energy increases?

What happens to an atom's kinetic energy as the temperature increases?

• Answer:

  Most people would answer your question as follows: As the temperature increases the atoms move faster, so their KE increases. Here is a story to illustrate what really happens!! Suppose you sit a glass of water on a heater vent. The air coming out of the heater vent is hotter than the water in the glass. The molecules in the hot air are moving fast (more KE). They collide with the molecules in the glass and make the molecules in the glass vibrate faster (more KE). The vibrating molecules in the glass collide with the water molecules next to the interior surface of the glass, causing the water molecules to move faster. (more KE). These water molecules hit other water molecules, making them move faster (more KE). These speedy water molecules hit the glass of the thermometer, making the glass molecules vibrate faster (more KE), hitting the fluid in the thermometer, making the molecules of fluid move faster (more KE). which makes the fluid expand and move up the thermometer. And after all this happens, you look at the thermometer sitting in the water and proclaim, "The water's temperature has increased!" My point is the temperature did not cause the KE of the atoms to increase. The other atoms that were moving faster and colliding with the water molecules caused the K.E. of the water molecules to increase!!