What is electronics?
Electronic devices can make sounds, send message, show pictures, measure, remember, calculate, and control. Machines made from wheels and levers can do some of these things, but they are often too slow and clumsy to do them well. Electricity can be used to power such machines, but this does not make them electronic. A machine can claim this title only if it contains devices in which the motion of the tiny particles called electrons that form electric currents can be directly influenced by electricity or magnetism. Devices of this kind allow electricity to control electricity itself. In a television set, for example, electricity form the aerial controls currents that paint pictures on the screen (pp. 44-45). In a computer, electrical changes caused by pressing keys control the power that writes data to a disk. Using electricity in this way makes it possible to do complicated things quickly and inexpensively. Ordinary machines are good for simple, repetitive jobs like drilling holes or drying hair. But if you want a versatile machine that can instantly change its behaviour in response to incoming information, you need electronics. A device like a radio can make a limitless range of sounds and a powerful electronic computer can conjure up an infinity of imaginary worlds.
What is electronics?Electronic devices can make sounds, send message, show pictures, measure, remember, calculate, and control. Machines made from wheels and levers can do some of these things, but they are often too slow and clumsy to do them well. Electricity can be used to power such machines, but this does not make them electronic. A machine can claim this title only if it contains devices in which the motion of the tiny particles called electrons that form electric currents can be directly influenced by electricity or magnetism. Devices of this kind allow electricity to control electricity itself. In a television set, for example, electricity form the aerial controls currents that paint pictures on the screen (pp. 44-45). In a computer, electrical changes caused by pressing keys control the power that writes data to a disk. Using electricity in this way makes it possible to do complicated things quickly and inexpensively. Ordinary machines are good for simple, repetitive jobs like drilling holes or drying hair. But if you want a versatile machine that can instantly change its behaviour in response to incoming information, you need electronics. A device like a radio can make a limitless range of sounds and a powerful electronic computer can conjure up an infinity of imaginary worlds.
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