Heat Transfer Method # 2:
Convection: Transfer of heat in a fluid (liquid or gas). Heated
fluids rise due to lower density. As the fluid cools, density
increases, and it sinks forming convection currents.
Examples: wind, sea breezes, water boiling, tectonic plates
shifting, ocean currents, air in our homes
Pictures of Heat Transfer via Convection
Heating Air in the Home
Boiling Water in a Pot
Ocean Currents
Wind and Ocean Breezes
Heat Transfer Method # 3:
Radiation: When electromagnetic energy (waves) transfer heat
into objects. This is the only way heat can transfer through
space.
Radiation Examples:
• Light waves from the sun travel through space, which heats
the surface of Earth.
• Microwaves vibrate water molecules, heating food
• Fire roasts marshmallows
• Lasers can heat metal
Examples of Heat Transfer Via Radiation
Light radiates through
empty space via the sun
Radiation from the fire
cooks the marshmallows
Food heats when microwaves
vibrate water molecules.
Light from the broiler
radiates heat to the fish and also heats
the surrounding air.
Example of all Three Types of Heat Transfer
Occurring Simultaneously