HEAT? What is that? Heat is the transfer of thermal energy from one object to another when two objects are brought into contact depends on the difference in temperature between the objects.
You know what? You cannot survive without heat. Actually, none of the creatures can. Plants need heat to photosynthesis, animals need plants to survive, and us people need animal and plants to survive. Not only because we don't have food, we will die to freeze. There is a movie called "Tomorrow". The movie shows the people die from cold, I mean extremely cold. I recommend this movie!
There are three ways of heat to be transferred. It is convection, condensation and radiation.
First, convection is the transfer of the thermal energy by the movement of atoms or molecules from one part of material to another. It is when the air or water become heated and rise up, the cold air or water falls back down where the heated air or water started from. If the cold air or water heats up again, it rises up and make the cycle. In real life, you can see convection when your mom boils the liquid to make food, or heating vent in the room can occur it. Did you ever wonder why air conditioner is high up near the ceiling and heating vent is at the bottom? It is because convection happens. If the air conditioner is at the bottom where heating vent is, the cold air won't rise up and try to stay on the bottom, and cycle won't work. Same reason as air conditioner, if heating vent is up in the room, where air conditioner is, hot air will try to stay up in the room. Oh, you know that convection occurs only with liquids or gas. What about solid? When the heat transfer occurs with solid, it is called conduction.
Conduction is transfer of thermal energy by direct contact. Not like convection, conduction occurs when the object is attached to the other object. For example, if you have a marshmallow and want to eat with the fire melting marshmallow, you have to stick the marshmallow on the stick and put directly in the fire. But!! if you feel that the stick is hot, you are holding a metal stick. The heat from the fire continuously heats up the the stick and the heat stretches out until where your hand is. So the heat from the fire touching the metal stick is called conduction. You might have not experienced burning your hand by melting marshmallow, and why is that? To be honest, market never sell metal stick for marshmallow so you don't burn yourself. I don't really know what substance it is, but there are some that conduction doesn't happens easily. The substance is plastic, feather, and fur. They are poor conductors of heat, and the reason is because of the molecules' formation. Metals have uniformed closed molecules but the other substances I mentioned are having strip like arrangement. So the distance the heat can transfer is so far, and that is why.
RADIATIONThe last, radiation is transfer of thermal energy without any object. The best example is the sun. Sun can heat up the house, but isn't it curious how it works without air or any object between? Radiation is the only way that it can transfer heat without any help. Not only the sun, but people also can have radiation to others since people also have heat inside, but it is just weak because the object that makes a heat which is us, doesn't have strong heat inside.
Do you know how the blanket keeps you warm? I am pretty sure you will wrap around the blanket to make yourself warm. Okay, so blanket doesn't make up heat. They only slow down the movement of the heat or they just prevents the heat. And that is how it works. Pretty simple right?
POP QUESTION! What will have more heat inside, the metal stick in the fire or glacier? Answer is at the bottom!
GLACIER
The answer is glacier! You are surprised aren't you? The stick in the fire is much smaller that glacier, which means they hold different amount of heat inside. Since glacier has more molecules, it is hotter, but it just doesn't show it is hot because it is so big. Stick shows out it is hot because it is small.
Done! Interesting isn't it?? I hope you enjoyed.
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