Amps Joules Volts Watts
Gas Liquid Solid Metal
Gas Liquid Solid Gas or liquid
Density changes as a hot substance expands Stirring a liquid with a motor Using a fan to blow air The force of attraction between particles
Microwave Infra-red Ultraviolet Nuclear fuel
By hot objects only By cold objects only By all objects all the time By shiny objects only
Shiny Shiny and white Dull Dull and black