1)     Thermal (infrared) radiation is the transfer of heat energy by EM waves

2)     Conduction is the main form of heat transfer in solids

 3)     Convection is the main form of heat transfer in liquids and gases

• Thermal radiation is emitted in solids, liquids, and gases. ANY object can both absorb and emit heat radiation, whether or not conduction or convection is also taking place
• The bigger the temperature difference, the faster heat is transferred between a body and its surroundings

THERMAL RADIATION

1)     All objects are continually absorbing and emitting heat radiation
2)     An object that’s hotter than its surroundings emits more radiation than it absorbs (as it cools down)
And an object that’s cooler than its surroundings absorbs more radiation than it emits (as it warms up)

CONDUCTION OF HEAT

Conduction – the process where vibrating particles pass on their extra kinetic energy to neighbouring particles

• In a solid, the particles are tightly packed together. So when one particle vibrates, it collides with other particles nearby and the vibrations quickly pass from particle to particle
• This process continues throughout the solid and gradually some…