Circuit Symbols

Circuit Symbols

​Who looks like they are finding it easier to build a circuit? Why do you think that?

​What is an electric circuit?

• ​An electric circuit is a path for electricity to flow.

• ​All electrical devices, like phones, contain electric circuits that allow them to work.

• ​You need 3 things for an electric circuit to work:

  • ​Source of potential difference (e.g. cell)

  • ​A component (E.g. Bulb, Motor)

  • ​A complete loop

​Why use circuit diagrams?

• ​Circuits are usually very complex

• ​It is important to have a clear way of showing how different components are connected together

• ​A standard set of symbols is used to represent different devices and to draw diagrams of circuits, which show how the components are connected.

​Full list of circuit Symbols

​Open Switch - Breaks the circuit

Closed Switch - Completes the circuit

Lamp - Transfers energy into light and thermal energy

Multiple Choice

What is this symbol?

• Open switch

• Closed Switch

• Lamp

• Switch

Multiple Choice

What is this symbol?

• Open switch

• Closed Switch

• Lamp

• Switch

Multiple Choice

What is this symbol?

• Open switch

• Closed Switch

• Lamp

• Switch

Cell - Provides potential difference to the circuit

Battery - 2 or more cells together

Diode - allows current to flow in ONLY one direction (infinite resistance in reverse direction)

Multiple Choice

What is this symbol?

• Diode

• LED

• Cell

• Battery

Multiple Choice

What is this symbol?

• Diode

• LED

• Cell

• Battery

Multiple Choice

What is this symbol?

• Diode

• LED

• Cell

• Battery

Resistor - Provides a fixed resistance to a circuit

Variable resistor - Provides a resistance that can be changed

LED - A diode that is light-emitting when current passes through it.

Fill in the Blanks

Name this Symbol

Fill in the Blanks

Name this Symbol

Fill in the Blanks

Name this Symbol

Fuse - The weakest part of a circuit. The wire inside will break if the current is too high

Voltmeter - Measures the potential difference in a circuit

Ammeter - Measures the current in a circuit

Draw

Draw a Voltmeter

Draw

Draw a Fuse

Draw

Draw an Ammeter

Thermistor - A temperature-sensitive resistor. The resistance changes depending on the temperature

LDR - A light dependant resistor. The resistance changes as the light intensity changes

Multiple Select

A component that changes resistance based on the light intensity

• Thermistor

• LDR

• Light dependant resistor

Multiple Choice

A component that changes resistance based on the temperature

• Thermistor

• LDR

• Light dependant resistor