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Thermal energy - Coggle Diagram
Thermal energy
Particle theory of conduction
When particles collide with each other thermal energy is passed along the particles. This is called thermal conduction
Metals are good thermal conductors. Electrons are free to move around.
Solid material when heated its particles starts to vibrate.
Liquids are poor conductors of as thermal energy is not transferred quickly.
Gases are poor conductors as particles are really far apart and thermal energy is not conducted very quickly.
Heat transfer by evaporation
Heat transfer by convection
Hot fluids rise and transfer thermal energy from one place to another. This is called convection
Hot air above burning candle rises and cold air replaces it. This is called convection current
Convection is the method of heat transfer in liquids and gases. Not in solids are particles are together.
Heat transfers by radiation
This is how thermal energy travels across empty space form the Sun to the Earth
Heat is transferred by radiation when it travels as an electromagnetic wave.
Emitting infra-red radiation
Sauce pans and metal kettles often have shiny outside surfaces to reduce heat losses by radiation
Hotter objects emits more infra-red radiation from its surfaces
Thermal energy and temperature. Temperature is measure in Celsius. Heat is form of energy and measured in joules.