2.3 Thermal Processes

Question 1

In what kind of materials can conduction occur?

Answer 1

Solids and liquids.

Question 2

Describe the process of conduction

Answer 2

• Solid/liquid is heated
• Particles vibrate more
• Energy is transferred to adjacent (beside) molecules via collisions, transferring energy from hot to cold regions

Question 3

In which materials can convection occur?

Answer 3

In fluids (liquids and gases).

Question 4

Describe the process of convection.

Answer 4

• When a section of fluid is heated, it becomes less dense
• This causes it to rise
• Denser fluid falls to take its place and is then heated, causing it to rise
• This sets up a convection current

Question 5

What kind of materials can transfer infrared radiation?

Answer 5

Any kind of material; it does not require a medium.

Question 6

What is infrared radiation?

Answer 6

It is an electromagnetic wave.

Question 7

What are the best absorbers of infrared radiation?

Answer 7

Black, dull surfaces.

Question 8

What are the best emitters of infrared radiation?

Answer 8

Black, dull surfaces.

Question 9

What factors affect the amount of IR emitted by a body?

Answer 9

• Temperature (higher = more IR)
• Surface area (larger = more IR)