Chapter 2 - Energy Transfer By Heating

Question 1

Thermal conductivity definition

Answer 1

How quickly energy is transmitted through it by thermal conduction

Question 2

How to test thermal conductivity

Answer 2

• 3 rods of different metals
• Wax on the end of each
• Faster the wax melts, the higher the thermal conductivity

Question 3

2 factors affecting the rate of heat loss from a building

Answer 3

1. Thickness of walls and roof
2. Thermal conductivity of the walls and the roof

Question 4

Thermal conductivity of the alls and roof can be reduced by using …………… …………….

Answer 4

Thermal insulators

Question 5

Energy transfer per second through a material depends on (3)

Answer 5

1. Material’s thermal conductivity
2. Temperature difference between the two sides
3. Thickness of material

Question 6

Temperature change of a substance depends on (3)

Answer 6

• Substance’s mass
• Type of material
• How much energy is transferred to it

Question 7

Specific heat capacity is defined as

Answer 7

The amount of energy needed to raise the temperature of 1kg of a substance by 1 degree

Question 8

Change in thermal energy equation =

Answer 8

Mass x specific heat capacity x temperature change

Question 9

Specific heat capacity unit

Answer 9

Joules per kilogram degrees Celsius

Question 10

In terms of infrared radiation - what happens if the temperature increases

Answer 10

Infrared radiation emitted increases

Question 11

For an object at a constant temperature
Infrared radiation emitted = ……….. ………… …………….

Answer 11

Infrared radiation absorbed