Bellringer
conduction, convection, or radiation
matching: use these definitions to you with the rest of the worksheet.

a. heat transfers when objects are in contact.
b. heat travels in rays or waves.
c. heated gas or liquid particles expand and rise.
label each example with the appropriate type of heat transfer: radiation, convection, or conduction. explain why you think so for each example (hint: use the definitions above to you).
1. heat we feel from the sun. why?
2. the heat you feel when you touch a hot stove. why?
3. heat you feel when you put your hands above a fire. why?
4. my spoon is hot after leaving it on the pot that was on the stove. why?
5. this is responsible for making macaroni rise and fall in a pot on the stove. why? 6. the heat a snake feels from the heat lamp above him. why?
7. transfer of heat by the actual movement of the warmed matter (i. e. gas or liquid). why?
8. the reason heating vents are usually placed on the floor of a home. why?
9. insulation is used to prevent this type of heat transfer. why?
10. this type of heat transfer is trapped by green houses. why?
11.why the dog lays down next to the wood stove. why?
12.why the kettle on the stove gets hot. why?
13. why you use a pot holder when getting the cookie sheet out of the oven.
14. heat you feel when you sit next to a campfire. why?
15. heat you feel from your electric blanket. why?

1. The heat from the sun is transferred through radiation. The sun emits electromagnetic waves in the infrared region. Because the transfer was through waves, look at your choices, the answer would be A. Radiation.

2. The transfer of heat through this method is done through conduction. You know that it is conduction because there was contact between objects. In this case, it is between the body part and the stove that it touched. The answer is then C. Conduction.

3. Like the sun, the heat is transferred trough electromagnetic waves from the fire through space. Again heat is transferred through waves. Because the fire is hotter than the space around it, the heat will travel to the colder space, where your hands are. The answer would then be A. Radiation.

4. The heat transfer is between three objects; the spoon; the pot; and the stove. Now all three of them are in contact. The stove heats up the pot, so the pot gets hot. The pot then transfers some of that heat to the spoon, which is also in contact with the pot. So the answer is C. Conduction.

5.Macaroni rise and fall in a pot on the stove because of the liquid that is surrounding it. The liquid is heated in the pot and when it warms up it expands and rises, carrying the macaroni with it. When it reaches the surface it cools down and goes back down, only to be heated again and rise. This is then considered as B. Convection.

6. You can picture the lamp above the snake as the sun. Because they are not touching each other, there is space in between the two. The lamp radiates heat towards the snake through waves that are travelling through the space in between them. The answer would then be letter A. Radiation.

7. The transfer of heat by the movement of the warmed matter would be convection. When gas or liquid warms up, it expands and rise and when it cools, it goes down causing a circular movement. If you put something in liquid that is boiling, you will see this action. The answer is B. Convection.

8. Heating vents are usually placed on the floor of a home because warm air tend to rise. Because of convection, warm air goes upwards and when it reaches colder surfaces or areas, they fall back down to the heating vents which will heat them up again. The answer is B. Convection.

9. Insulation prevents heat transfer through conduction. This is done by putting a space in between objects to prevent direct contact or at least impede the transfer of energy. For example, when you wear oven mitts while getting a hot pot or baking pan from the oven. The mitts are poor conductors of heat, so it impedes the transfer of energy from one object to the other. The answer is B. Convection.

10.Green house trap heat that is radiated by the ground or the objects below it. As the ground heats up, it reflects the energy back up, but greenhouses keep the warm air that the ground has heat up. This warm air then gets trapped inside the greenhouse, which is why it is warm inside them. The answer is A. Radiation.

11.The heat that is emitted from the wood stove is used as a source of heat for the dog. The wood stove is radiating heat through waves. The dog is keeping itself warm by staying within the path of the waves. It’s like how campers huddle around a campfire at night to keep warm.  The answer is A. Radiation.

12.The kettle on the stove gets hot because the kettle is in contact with the stove which emanates heat. The heat from the stove is transferred to the kettle. The fire from a stove is hotter than the kettle, so the heat travels to the colder object, which is the kettle. The answer is C. Conduction.

13. You use a pot holder when you get the cookie sheet out of the oven because you do not want to get burned. Pot holders are not good conductors of heat, or in other words, heat does not travel well through them. By putting them on, you are preventing the heat from the cookie sheet from travelling to your hands. The answer is C. Conduction.

14. The heat that you feel when you sit next to a campfire travels through radiation. The energy travels in waves through the space in between you and the fire. Because the air around it is colder than the fire itself, the heat goes towards the colder area. The answer is A. Radiation.

15. The heat that you feel from your electric blanket is transferred to you via conduction. Let us presume that your electric blanket is already warmed up. Now you receive its heat when you are in contact with the warm electric blanket. This answer is C. Conduction.