Electrical Circuits

Circuits:

A circuit is made up of a power supply, connecting wires & various elements that allow current to leave a power source, travel through the elements & return back to the power source.

Common Electric Parts

Battery/Power Source

Bulb

Common symbols (cont’d)

Switch

Push-button Switch

Resistor

Voltmeter

Ammeter

V

A

Circuits

Power Supply

Resistor

A

Ammeter

v

Voltmeter

- +

Types of Circuits:

There are 2 types of circuits: 1. Series Circuit 2. Parallel Circuit

SERIES

Trick to help identify type of circuit:

Series: Current has only one option to flow

Parallel: Current has more than one option to flow through

PARALLEL

Series Circuits

Components are connected end to end

Current only follows one path If one part of the circuit is broken,

the entire circuit will stop functioning

Eg: Christmas tree lights

Parallel Circuits

Circuit that contains at least one branch

Current can follow at least 2 different paths

If part of the circuit is defective another part may still be able to operate.

Eg: headlights on a car

Series or Parallel?

AA

SERIES

SERIES

PARALLEL

PARALLEL1.

4.3.

2.

Adding an Ammeter into a Circuit

In order to measure the current traveling through a circuit, an ammeter must be inserted into the circuit.

An ammeter is always connected inside the circuit in series.

A

In each diagram, is the ammeter hooked up correctly to these circuits?

Connecting An Ammeter

A

A

A

A

A A

Adding a Voltmeter to a Circuit

In order to measure the voltage traveling through a circuit, a voltmeter must be inserted into the circuit.

A voltmeter is always connected outside the circuit in parallel.

V

In each diagram, is the voltmeter hooked up correctly to these circuits?

Connecting A Voltmeter

VV

V

V

V

V

KEY POINTS

Voltmeter – always placed outside of circuit attached in parallel

Ammeter – is always placed inside circuit attached in series

Setting up a Circuit

PARV acronym P-ower A-mmeter R-esistor V-olt Meter