Thermal radiation

Question 1

What is Thermal radiation

Answer 1

Transfer of energy by heating Infrared electromagnetic waves

Question 2

how does thermal radiation work

Answer 2

All objects are continually emitting and absorbing Infrared radiation

An object that’s hotter than it surroundings emits more radiation than it absorbs

An object that’s cooler than it surroundings absorbs more radiation than it emits

Question 3

How does colour affect thermal radiation

Answer 3

The darker the color the better it is at absorbing and emitting radiation(black)

Question 4

How does the shininess of a surface affect thermal radiation

Answer 4

The duller the surface he better it is at absorbing and emitting radiation(matt)

Question 5

How to reduce thermal radiation

Answer 5

Designed a surface that is a poor emitter (shiny and white)

Question 6

What is a Leslie cube

Answer 6

Leslie cube is hollow, watertight metal cube. 4 vertical faces have different surfaces (white, dull, etc.)

Question 7

How to investigate the emission of thermal radiation

Answer 7

1. Place a Leslie cube on a heatproof mat
2. Fill the cube with boiling water
3. Wait, then put thermometer against the 4 sides (should all be the same temp)
4. Hold Infrared detector 10 cm away from one face and record amount of IR radiation
5. Repeat for each face