GCSE Physics P2: Energy transfer by
heating
Thermal conductivity - Answer Property of a material that determines the energy
transfer through it by conduction
Thermal insulator - Answer A material that has a low thermal conductivity, and low
energy transfer
-low thermal conductivity of the insulating material
-as thick as practically possible - Answer Ways to reduce energy transfer per second (2)
Temperature difference, thickness, thermal conductivity - Answer Factors that the
energy transfer per second through a layer of insulating material depend on
diamond, silver, copper, gold, metals - Answer Good thermal conductors (5)
wood, fiberglass, air, wool - Answer Good thermal insulators (4)
Infrared radiation (IR) - Answer Electromagnetic waves between visible light and
microwaves in the electromagnetic spectrum.
Black body radiation - Answer The radiation emitted by a perfect black body (a body
that absorbs all the radiation that hits it)
A perfect black body - Answer An object that absorbs all the radiation that hits it, doesn't
reflect any radiation and no radiation passes through it.
Temperature increases - Answer When an object absorbs radiation faster than it emits
radiation
Constant temperature - Answer The object emits infrared radiation at the same rate as it
absorbs it.
Light, shiny surfaces - Answer Poor absorbers and emitters of infrared radiation
Dark, matt surfaces - Answer Good absorbers and emitters of infrared radiation
the rate light and IR from the sun are:
-reflected into space or absorbed in the the earth's surface or atmosphere
-emitted from the earth's surface and atmosphere - Answer Earth's temperature
depends on... (2)
Greenhouse gases - Answer absorb infrared radiation and then emit it back to the
earth's surface
heating
Thermal conductivity - Answer Property of a material that determines the energy
transfer through it by conduction
Thermal insulator - Answer A material that has a low thermal conductivity, and low
energy transfer
-low thermal conductivity of the insulating material
-as thick as practically possible - Answer Ways to reduce energy transfer per second (2)
Temperature difference, thickness, thermal conductivity - Answer Factors that the
energy transfer per second through a layer of insulating material depend on
diamond, silver, copper, gold, metals - Answer Good thermal conductors (5)
wood, fiberglass, air, wool - Answer Good thermal insulators (4)
Infrared radiation (IR) - Answer Electromagnetic waves between visible light and
microwaves in the electromagnetic spectrum.
Black body radiation - Answer The radiation emitted by a perfect black body (a body
that absorbs all the radiation that hits it)
A perfect black body - Answer An object that absorbs all the radiation that hits it, doesn't
reflect any radiation and no radiation passes through it.
Temperature increases - Answer When an object absorbs radiation faster than it emits
radiation
Constant temperature - Answer The object emits infrared radiation at the same rate as it
absorbs it.
Light, shiny surfaces - Answer Poor absorbers and emitters of infrared radiation
Dark, matt surfaces - Answer Good absorbers and emitters of infrared radiation
the rate light and IR from the sun are:
-reflected into space or absorbed in the the earth's surface or atmosphere
-emitted from the earth's surface and atmosphere - Answer Earth's temperature
depends on... (2)
Greenhouse gases - Answer absorb infrared radiation and then emit it back to the
earth's surface
