Please enable JavaScript.
Coggle requires JavaScript to display documents.
P2 Energy Transfer by Heating (Heating and Insulating Buildings (Loft…
P2 Energy Transfer by Heating
Energy Transfer by Conduction
The higher the thermal conductivity of a material, the higher the rate of energy transfer through it
The thicker a layer of insulating material, the lower the rate of energy transfer through it
Non-metal materials such as wool and fiberglass are the best insulators
Metals are the best conductors of energy
Infrared Radiation
Black body radiation is radiation emitted by a body that absorbs all the radiation incident on it
The hotter an object is, the more infrared radiation it emits in a given time
All objects emit and absorb infrared radiation
More about Infrared Radiation
The Earth's temperature depends on a lot of factors such as:
Absorption of infrared radiation from the Sun
The temperature of an object increases if it absorbs more radiation than it emits
The emission of radiation from the Earths surface and atmosphere
Specific Heat Capacity
The greater the mass of an object, the more slowly its temperature increases when it is heated
To find the specific heat capacity of a substance, use a joulemeter and a thermomenter to measure the change in energy and temperature for a measured mass, and then rearrange the equation and use it
Change in energy = mass x specific heat capacity x change in temperature
The specific heat capacity of a substance is the amount of energy needed to change the temperature of 1 kg of the substance by 1 degree Celsius
Heating and Insulating Buildings
Loft insulation
Cavity wall insulation
The rate of energy transfer from houses can be reduced by using:
Double-glazed windows
Electric and/or gas heaters and gas or oil-fired central heating or solid-fuel stoves are used to heat houses
Aluminium foil behind radiators
External walls with thicker bricks and lower thermal conductivity
Cavity wall insulation is insulation material that is used to fill the cavity between the two brick layers of an external house wall