1. Heat Transfer- A Closer Look

2. Review From last class…
Did you…?
Finish the Heat Transfer Graphic Organizer
Put your name on it and hand it in
Finish the Google Forum Quiz (still open to complete)
What are some similarities of Conduction, Convection and Radiation?
What are the differences?
What are examples of each?

3. Conduction & Particle Theory
Conduction is the transfer of heat between substances that are in DIRECT contact with each other
The better the conductor, the more rapidly the heat will transfer

4. Conduction & Particle Theory
In solids, particles are very close to one another and heat transfer is made directly from one particle to another
Thermal conduction is the process of energy transfer by DIRECT collision between particles

5. Conduction & Particle Theory
Particles that are hotter move faster and collide with slower moving particles causing them to speed up as well
This continues until the object is evenly heated

6. Conductors & Insulators
Objects that transfer heat quickly are called Conductors
Ex: metals
Objects that are poor conductors of heat are called Insulators
Ex: glass, wood, brick, stone, fibreglass, styrofoam

7. Convection & Particle Theory
Convection is the movement of heat in a GAS or LIQUID (Fluid)
When a fluid is heated it becomes less dense and becomes lighter so it rises
The colder fluid is more dense and heavier and sinks to the bottom to take the place of the gas or liquid that has risen

8. Convection & Particle Theory
The circular current that is created in a fluid that has been heated is called a CONVECTION CURRENT

9. Radiation and Particle Theory
Radiant Energy can take many forms:
Radiowaves
Microwaves
Visible light waves
Xrays
Sources of radiation: Hot Objects

10. Radiation and Particle Theory
All forms of radiant energy (radiation) have common characteristics
They travel in waves or rays
They can be absorbed or reflected
They can travel through space (vacuum) at a speed of km/sec

11. Animations & Study