What makes obects/substances hot?

Question

Example:Why does sand get hot? How does sand get hot?

Answer 1

Temperature is a measure of the average heat of the molecules of a substance. Basically, it is how fast the molecules are vibrating or moving. In gases the atoms or molecules actually fly around, but in liquids and solids they vibrate in a small area. Faster vibration equals hotter. if you have a pan with water in it and you put it on the stove, the burning gas from the stove will hit against the bottom of the pan. The atoms of the metal in the pan will vibrate faster and bump against the water. The water molecules will start moving around faster and faster and eventually be moving so fast they will fly out of the pan as steam.

Objects like sand, that are out in the sun, receive energy in the form of radiation. The light waves from the sun bump against the sand molecules and they start vibrating faster. Some objects are able to absorb the radiation more easily... you may have noticed that dark colored objects absorb heat faster than light colored objects. That's because the dark objects absorb the heat and the light objects reflect it.

When you get to the course called 'physics' in high school you will study about heat and energy.