Y7 Wk 36 Heat and heat transfer
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Acep science, term 2, Heat Transfer
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- 1. Heat and Heat Transfer Pg. 126- 130
- 2. Heat is more than hot or cold Heat is: ENERGY TRANSFER from
a higher temperature to a lower temperature. Energy in the form of
heat always flows from HOT to cold. Activity: Look at the picture,
in your notebook draw the energy flow from the higher temperature
object to the lower temperature object.
- 3. Textbook page 126, exercise #7 Draw an arrow to show the
direction of energy flow. Remember, energy flows from HOT to
Cold
- 4. Measuring Heat One way of measuring heat is the calorie
(cal). * In nutrition, 1 C (a Kilocalorie) is equal to 1000
calories. * One calorie (cal) is equal to the amount of energy
needed to raise the temperature of 1 g of water by 1oC. Heat is
energy flow. Thermal Energy is the total Kinetic Energy of a
substance. Temperature is the average Kinetic Energy of a
substance.
- 5. Conductor: Metal Wire Heat Transfer Liquid Beaker A = 85oC
Beaker B = 15oC Beaker A has a higher temperature. 85oC Heat will
transfer from Beaker A to Beaker B (by conduction using the metal
wire). Heat will transfer until both beakers are the same
temperature. Beaker B will have MORE THERMAL energy because it
has
- 6. HEAT How do you touch hot food or other hot items? Write
down materials you use to touch hot items without burning yourself:
1. 2. 3.
- 7. Conductors and Insulators Insulators are materials that are
poor conductors of heat. These keep objects hot (or cold), but not
your hands! Examples: wood, plastic foam, paper Conductors are
materials that transfer heat very well. These objects will transfer
heat fast from the object to your hand. Example: Metals
- 8. Activity Pg. 129, #12 in textbook
- 9. Heat Transfer There are 3 types (Conduction, Convection,
Radiation) HEAT is the flow of energy from a higher temperature
object to a lower temperature object. VIDEO please click to listen
and watch an online Prezi about the 3 types of Heat Transfer. **Can
you explain the last picture in the video?**
- 10. Heat Transfer 1: Convection Click the above link to see
Convection of a gas. Convection also works for liquids! click for
the video! Add Energy (in the form of heat from a higher
temperature object). The particles of a substance (gas or liquid)
will move faster and spread apart, which makes them less dense.
They will rise up. They have more kinetic energy. When they begin
to cool, the particles move slower and move closer together, which
makes them denser. They
- 11. Heat Transfer 2: Conduction When a higher temperature
object is in contact (touching) a lower temperature object, heat
will flow from the hotter object to the cooler object. This is
Conduction! In the photo to the left, which letter demonstrates
conduction? A: The burner is in contact with the kettle and the
flame.
- 12. Conduction Continued This is a polar bear hair. There is
air in the middle. This is a good insulator. This helps to keep the
bear warm.
- 13. Heat Transfer 3; Radiation Radiation is heat transfer
through electromagnetic waves. There is no direct contact
(touching) between the higher temperature object and the lower
temperature object. An example is the SUN. It warms the earth
through radiation.
- 14. Summary of Heat Transfer: Convection of liquid
- 15. Quiz 1. What is the difference between an insulator and a A
conductor has particles that transfer heat quickly. conductor? has
particles that do not transfer heat quickly. An insulator 2. What
Heatis used to measure heat? unit is measured in calories (cal). 3.
If a substance No it may not. It has to have many molecules.
Tempera has a higher temperature, does it is the average kinetic
energy of a substance. Thermal E also have greater kinetic energy
of a substance. thermal energy? total 4. List 3 types of Heat
Transfer. Conduction, Convection, and R When two objects of
different temperatures are in contact, which conduction. Conduction
demonstrate? This demonstrates heat transfer does this transfers
heat by two 5. After a period of time, the temperatures of both
objects will be th