Keep it hot or cold.

This week, we study about thermal energy. Thermal energy can make things hot or cold. Your hot plate, stove, freezer and ice cubes all make thermal energy. These things can also make some objects get hot or cold.

If you leave your aluminum coke can in the refrigerator, it's going to get really cold. If you go outside in the summer time with no shoes on, your feet will probably get burned on the concrete. If you pour hot chocolate into your glass cup, the cup will start to get warm. All of these objects get hot and cold easily because they are conductors. Thermal energy moves through them, and they can get hot and cold really easily. Energy from the sun transfers to the concrete, and it causes the temperature to increase.

When you go outside in the summer time, your car feels really hot, but the trees aren't as hot as your car. Trees are made out of wood, and wood is an insulator. When you hold a plastic spoon in your hand, your thermal energy from your hand doesn't make the plastic very warm. Plastic is also an insulator. Thermal energy does not go through insulators easily, so they don't get as hot or cold as conductors.

Look at the picture above. Which objects are the best conductors, and why? Which objects are the best insulators, and why?

Watch this brainpop video about heat!