Energy Stores, States of Matter, and Heat Transfer

Vocabulary flashcards covering energy stores and transfers, efficiency, states of matter, heat transfer mechanisms, radiation, and energy resources.

Energy stores

CEMENT KG (chemical, electrostatic, magnetic, elastic potential, nuclear, thermal, kinetic, gravitational potential)

Energy transfers

Mechanical (force), waves (sound and light), electric current, heating.

Law of conservation of energy

Energy cannot be created or destroyed, it can only transfer between stores.

Dissipation

Energy spreads out to the surroundings.

Methods for improving efficiency

(1) Lubricate to reduce friction; (2) use low resistance wires; (3) streamline to reduce air resistance; (4) reduce vibration.

Particle

An atom or molecule.

Solid

State where particles are in a lattice, vibrating around fixed positions.

Liquid

State where particles can move and slip across each other.

Gas

State where particles move in random directions at varying speeds.

Plasma

Charged gas particles; the most common state of matter in the Universe.

Fluid

A liquid or a gas.

Conduction

Thermal transfer in a solid, due to the relay of particle vibrations.

Convection

A circulating current in a fluid, caused by density changes as the thermal store changes.

Direction of heat transfer

Towards the cold.

Thermal radiation

Infrared waves, part of the electromagnetic spectrum.

Best absorbers and emitters of infrared

Matt and dark-coloured surfaces.

Worst absorbers and emitters of infrared

Shiny and light-coloured surfaces.

Perfect black body

An object which absorbs all the radiation that hits it (e.g. a star).

Black body radiation

Radiation emitted by a black body.

Renewable energy source

A source which can be replenished.

Non-renewable energy sources

Coal, oil, gas, nuclear fuel for fission.

Renewable energy sources

Solar, wind, wave, tidal, hydroelectric, geothermal, biomass.