Electrical Symbols and Functions

Fuse

Safety device that prevents too much current flowing through the circuit. Too much current the fuse will melt and break making the circuit incomplete and stopping the flow of electrons

Cell

Supplies electrical energy. The lighter (on the left) is positive

Battery

Supplies electrical energy. A battery is more than one cell

Power pack

Supplies electrical energy. Voltage can be set to a desired value

Wire

To pass current very easily from one part of a circuit to another

Switch

An on-off switch allows current to flow only when its is in the closed (on) position

Lamp

A lamp converts electrical energy to light

Resistor

A resistor restricts the flow of current and changes electrical energy to heat energy

Rheostat ( Variable Resistor )

A Rheostat is usually used to control the current in a circuit

Voltmeter

A voltmeter is used to measure voltage

Ammeter

An ammeter is used to measure current

Ohmmeter

Used to measure resistance. Most measure resistance