There are three main methods of heat transfer: conduction, convection, and radiation. Conduction occurs through direct contact between solid objects as particles vibrate and collide. Convection involves the transfer of heat by fluid movement, as warmer liquid or gas rises and cooler moves down. Radiation emits electromagnetic waves that carry heat energy away from hot surfaces, with dull black surfaces absorbing heat better than shiny bright surfaces.

1. METHODS OF HEAT
TRANSFER

3. HOW DOES HEAT TRANSFER
THROUGH CONDUCTION?
 Conduction takes place due to
the vibrating and colliding
particles of object that are in
contact.
 It can take place in solids,
liquids and gases but it takes
place best in solids.

4. CONDUCTION
Conductivity – ability to conduct
or absorb heat.
 Thermal conductors – objects
that absorb heat
 Thermal insulators – poor
conductors of heat

7.  Conduction takes place only in
fluids (liquid and gas) because
their particles can move around.
The heat is transferred by the
particles themselves.
 During convection, warmer liquid
or gas expands and goes up while
cooler liquid or gas moves down.
HOW DOES HEAT TRANSFER
THROUGH CONVECTION?

10.  Radiation refers to emission of
electromagnetic waves which carry
energy away from the surface of
the emitting body or object.
 Different surfaces emit or absorb
heat differently. Dull and black
surfaces absorb heat better than
bright and shiny surface.
HOW DOES HEAT TRANSFER
THROUGH RADIATION?

11. RADIATION
 Thermal or Infrared Radiation –
objects emit and absorb
radiation (depends on the
temperature of the emitting
object, the hotter an object is
the more infrared radiation
emits).