Physics Energy Test

Energy Transferes

Thermal - Heat (Radiators, flames)

Electrical - (Moving/static electric charges)

Sound - (Musical instruments, megaphones)

Light - (Sun, bulbs, candles)

Energy Stores

Chemical - (Food, fuel, batteries)

Nuclear - (Nuclear power stations)

Kinetic - (Moving objects, runner, cars)

Elastic Potential - (Springs, rubber band etc)

Gravitational Potential - (Resultant of vertical position: parachutist, apple on tree)

-Energy is measured in Joules

-Efficiency = useful energy output/ total energy input. Efficiency equation= useful energy/input energy x100%

Conduction

Heat energy can move through a substance by conduction, the particles have to be touching . Metals are good conductors of heat, but non-metals and gases are usually poor conductors of heat. Poor conductors of heat are called insulators. Heat energy is conducted from the hot end of an object to the cold end.

Convection

Convection occurs when particles with a lot of heat energy in a liquid or gas move and take the place of particles with less heat energy. Heat energy is transferred from hot places to cooler places by convection.

The liquid or gas in hot areas is less dense than the liquid or gas in cold areas, so it rises into the cold areas. The denser cold liquid or gas falls into the warm areas. In this way, convection currents that transfer heat from place to place are set up. (EVERYDAY EXAMPLE: RADIATORS AND HEAT)

Radiation

All objects give out and take in …