➽ ENERGY - Energy transfer: radiation

Question 1

What is infrared?

Answer 1

Type of radiation similar to light.

Question 2

How does radiation travel?

Answer 2

As transverse waves.

Question 3

What makes radiation different to conduction and convection?

Answer 3

1. Radiation doesn’t require particles to travel.
2. Thus radiation can travel in space but conduction and convection can’t.

Question 4

What objects emit infrared radiation?

Answer 4

All objects, the hotter the object, the more infrared it emits.

Question 5

What 3 things determine how much infrared is emitted?

Answer 5

1. Temperature of object
2. Surface type of object
3. Colour of object

Question 6

What 3 things can happen to infrared when it comes in contact with another surface?

Answer 6

1. Transmitted
2. Absorbed
3. Reflected

Question 7

How can infrared be detected?

Answer 7

1. Your skin absorbs and detects it as heat
2. Thermal imaging cameras
3. Remote thermometer that use infrared radiation to detect temperature.

Question 8

What is the relationship between dark colours and infrared?

Answer 8

Dark colours absorb more infrared. This causes them to heat up faster.

Question 9

What is the relationship between light colours and infrared?

Answer 9

Light colours reflect more infrared. This keeps them cooler longer.

Question 10

What is the relationship between shiny surfaces and infrared?

Answer 10

Shiny surfaces reflect more infrared. This keeps them cooler longer.

Question 11

What is the relationship between matt surfaces and infrared?

Answer 11

Matt surfaces absorb more infrared. This causes them to heat up faster.

Question 12

Give an example of use of reflecting infrared.

Answer 12

Foil blankets are used after marathons or on the rescued people from a burning building to prevent rapid heat loss as this could make them ill.