Law of conservation of energy

physics science revision

types of heat transfer

conduction, convection, radiation

conduction

requires contact, works best in solids

convection

works best in liquids and gas, requires movement of currents ( heat particles rise, cooler particles fall the cycle repeated until all particles are heated)

radiation

requires no medium to travel, it is infrared radiation (rays)

law of conservation of energy

energy cannot be created nor destroyed, it can only be transferred or transformed.

energy transfer

when energy moves from one object to another and does not change its form

energy transformation

when one form of energy is changed/converted into another form of energy

heat

transfer of energy from one region to another region with lower temperature

calculate energy efficiency

useful energy/total energy X 100 = —-%

what is energy efficiency

never 100% efficient as some energy is always wasted in the process