Switches

A switch is made by introducing a gap into a circuit. When the gap is closed, the switch is on, the circuit complete and current flows.

Short circuits

A short circuit is not a good idea! This occurs when the two ends of a battery are joined directly by a wire, without a bulb, buzzer or something similar in the circuit. A very large current results which makes the wires very hot and it quickly results in a flat battery.

Circuit diagrams

It is much easier to record circuits when circuit diagrams are used. There are various accepted symbols.

An effective way of demonstrating to children the usefulness of circuit diagrams is to ask them to draw a circuit so that it can be recorded for posterity. This will take them ages and will probably develop into quite a work of art. If circuit diagrams are introduced after this laborious process they will be greeted with some relief.

Contents

Safety, Static Electricity
Charge
Current Electricity, Making a bulb light, Models
Atomic Theory
Conductors and insulators
Current, Voltage
Electrical circuits
Measuring current
Resistance
Power
Assessment/Discussion Material
Reference Material