Yr9 - electricity and circuit basics

14
Dr Pusey www.puseyscience.com

Transcript of Yr9 - electricity and circuit basics

Dr Pusey

www.puseyscience.com

DefinitionsElectricity = The flow of charge

through an electrical conductor

Circuit = a path through which electricity flows

What are the requirements for a circuit?

Power source, produces a charge imbalance

Complete path of conducting material

Two main types of circuit

Series

Parallel

Important WordsVoltage

The potential for electricity to flow.

Measured in Volts

Water Analogy: The amount of pressure pushing the water through the pipe

http://hyperphysics.phy-astr.gsu.edu/hbase/electric/watcir2.html

Important WordsCurrent

The flow of charge through a conductor

Measured in Amperes/Amps

Water Analogy: The amount of water that water rushes through the pipe per second.

http://hyperphysics.phy-astr.gsu.edu/hbase/electric/watcir2.html

Important WordsResistance

The resistance to the flow of current through a conductor

Measured in Ohms

Water Analogy: The size of the pipe

http://hyperphysics.phy-astr.gsu.edu/hbase/electric/watcir2.html

More about Components Batteries are the power source. A circuit will not

work without a battery.

Resistors restrict the current. Variable resistors can change resistance, like a dimmer switch for your light

Voltmeters measure the voltage applied to something. They must be on the outside of the circuit

Ammeters simply tell you how much current is going through them, so they need to be inside the circuit

Lamps convert electricity into light energy. The more current, the brighter the light!

Circuit symbols

DRAW THIS!

V

A

Open Switch

Closed Switch

Light (Lamp)

Ammeter

Voltmeter

Fuse

Battery Cell

Resistor

Variable Resistor

Example 1 Turn this picture into a circuit diagram using the

appropriate symbols

Example 2 Turn this picture into a circuit diagram using the

appropriate symbols

Example 2 Turn this picture into a circuit diagram using the

appropriate symbols

Example 3 Label the following circuit diagram

Example 3 Label the following circuit diagram

Quick Quiz Draw the circuit for a torch. Include a battery, a lamp

and a switch.

Quick Quiz Draw the circuit for a torch. Include a battery, a lamp

and a switch.