Heat and Thermodynamics II - SS1 Physics Past Questions and Answers - page 3

Conduction is the transfer of heat through direct contact between particles of a substance. It occurs when the particles gain energy and vibrate, transferring that energy to neighbouring particles. This process continues until thermal equilibrium is reached. 

Examples of conduction in everyday life include:

• Touching a hot stove and feeling the heat transfer from the stove to your hand.

• Placing a metal spoon in a cup of hot coffee, where heat is conducted from the coffee to the spoon.

• Walking barefoot on hot sand, where heat is conducted from the sand to your feet.

Convection is the transfer of heat through the movement of fluid or gas. It occurs when warmer particles rise and cooler particles sink, creating a cycle of fluid motion. Convection allows for the transfer of heat over larger distances.

Real-world examples of convection include:

• Boiling water in a pot, where heat is transferred from the bottom of the pot to the water through convection currents.

• Heating a room with a radiator, where warm air rises, creates convection currents that distribute heat throughout the room.

• Ocean currents, where warm water near the equator rises and cooler water from the poles sinks, create a global convection system.