P2 Flashcards
What are the best conductors
Metal
What are the best insulators
Wool and fibreglass like materials
How does thermal conductivity effect the rate of energy transfer through a material
The higher the thermal condunctivity of a material, the higher the rate of energy transfer through it
Hiw does the thickness of insulating material effect the rate of energy transfer through it
The thicker the layer, the lower the rate of energy transfer through it
How do object interact with infrared radiation
All objects emit and absorb infrared radiation
How does heat effect the amount of infrared radiation emitted
The hotter the object is, the more infrared radiation the object emits in a given time
How does the temperatire of an object increase
If it absorbs more radiation than it emits
What does the Earth’s temperatire depend on
Absorbtion of infrared radiation from the sun
Emission of infrared radiation from the surface of the Earth and it’s atmosphere
What is the specific heat capacity of an object
The amount of energy needed to change the temp of 1kg of the sunstance by 1°C
What is the equation of specific heat capacity
🔺E = m x c x 🔺t
Change in energy = mass x specific heat capacity x change in temp
How does mass effect effect time taken for temperatire to increase
The greater the mass of the object, the more slowly its temperature increases when its heated
What appliances can be hsed to heat a house
Electric and/or gas heaters
Gas or oil-fired central heating
Solid-fuel stoves
What strategies can be put in place to reduce heat loss from a house (5)
Loft insulation Cavity wall insulation Double glazed windows Aluminium foil behind radiators External walls or thicker bricks and lower thermal conductivity
What is cavity wall insulation
Insulation material that is used to fill the cavity between the 2 brick layers of an external house wall
