The components in a home audio/video system are pretty complicated to anyone without a good understanding of electronics; but wire–good, old-fashioned wire–is something we can all understand. It’s ...

Key learning points Electrical charges What are free electrons? Cell polarity Conventional current direction Electrons orbit the nucleus. An atom has a neutral charge, because it contains the same ...

For electricity to flow, everything needs to be connected in a big ring. It’s called a circuit. For example, the lights in most houses and flats are part of a circuit controlled by the consumer unit, ...