Heat Energy and Heat Transfer
Designed by Dr T. Marlow
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You need to know about infrared radiation:
a) All objects emit and absorb infrared radiation.
b) The hotter an object is the more infrared radiation it radiates in a given time.
c) Dark, matt surfaces are good absorbers and good emitters of infrared radiation.
d) Light, shiny surfaces are poor absorbers and poor emitters of infrared radiation.
e) Light, shiny surfaces are good reflectors of infrared radiation.
You also need to know about kinetic theory:
a) The use of kinetic theory to explain the different states of matter.
b) The particles of solids, liquids and gases have different amounts of energy.
c) The factors that affect the rate of evaporation and condensation.
d) The transfer of energy by conduction, convection, evaporation and condensation involves particles, and how this transfer takes place.
You also need to know about heat transfer:
a) The rate at which an object transfers energy by heating depends on:
■ surface area and volume
■ the material from which the object is made
■ the nature of the surface with which the object is in contact.
b) The bigger the temperature difference between an object and its surroundings, the faster the rate at which energy is transferred by heating.