6.+Chloe


 * __How heat moves__**


 * Radiation** happens when heat moves as energy waves, which are called infrared waves. They move directly from one source to the other. This is how the heat of the sun moves to the earth. When the heat waves hit a cooler object, the molecules of the cooler object speed up, which makes the object become hotter.


 * Conduction** is another way that heat can move. When heat comes in contact with matter (anything you can touch physically) it makes the atoms and molecules move. Once atoms or molecules are moving, they collide with other atoms or molecules, making them move as well. Then these bump into other molecules and make them move, and so on. In this way, the heat is transferred through matter.


 * Convection** happens when a substance that can flow, like water or air is heated in the presence of gravity. When air or water is in the presence of gravity, the gravity pulls all of it down. When there is heat at the bottom of this air or water, the molecules in contact with the heat start to move, spreading apart. The heated air or water becomes less dense. It rises up to reach air or water with the same density it has, and it gets there, it pushes the air or water that was there out of the way. At the same time, new air or water fills the space that was vacated when the heated molecules rose up. The air or water that gets pushed out of the way falls down, setting up a circular motion. Air or water is heated at the bottom, travels to the top, cools, gets denser, falls, is heated again and the whole cycle starts again. Convection does not occur in space because there is no gravity.

My device that uses radiation is a cellphone.

My device that uses conduction is a pot. Conduction is what makes a pot handle hot when only the bottom is touching the stove.

My device that uses convection is an oven. The heating coils at the bottom of the oven heat the air which climbs to the top, cools slightly, and falls down again.

By Chloe

__Heating experiment__
This experiment showed that smaller amounts of water and oil heat faster than bigger amounts.