P2 Energy Transfer By Heating Flashcards
What are the best conductors of energy?
Metals
What are the best insulators?
Non-métal materials such as wool and fibreglass
What is the correlation between the thermal conductivity of a material and the rate of energy transfer through it?
The higher the thermal conductivity of a material the higher the rate of energy transfer though it
What is the relationship between the thickness of a material and the rate of energy transfer through it?
The thicker a layer of insulating material, the lower the rate of energy transfer through it.
Do all objects emit and absorb infrared radiation.
Yes
What is the relationship between how hot an object is and how much infrared radiation it emits at a given time.
The hotter an object is the more infrared radiation it emits in a given time
What is black body radiation?
Black body radiation is radiation emitted by a body that absorbed all the radiation incident on it.
How does the temperature of an object increase?
It increases if it absorbs more radiation than it emits
What are the factors the earths temperature depends on?
The absorption of infrared radiation from the sun
The emission of radiation from the earths surface and atmosphere
What are used to heat homes?
Electric and/or gas heater and gas or oil fired central heating or solid fuel stoves are used to heat houses.
The rate of energy transfer from houses can be reduced by using:
Loft insulation Cavity wall insulation Double-glazed windows Aluminium foil behind radiators External walls with thicker bricks and lower thermal conductivity
What is cavity wall insulation?
Cavity wall insulation is insulation material that is used to fill the cavity between the two brick layers of and external house wall
