Electronics Calculations Data Handbook

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Circuits and components

Conductors and insulators

Why do some materials conduct electricity, while others don’t? Some materials are populated by good and careful atoms which don’t lose their electrons easily (and probably feel ashamed if they do). Hence the itinerant population is low. The few free electrons that exist tend to sit miserably in one place, having given up hope of ever finding a home. These are insulators, typically air, rubber or the fibreglass backing of a circuit board. In other materials atoms are positively feckless. There are many free electrons and should some charged material come near they move accordingly. How do they know? They feel the voltage. These are conductors. Most metals are conductors. We use copper a great ...