Transcript Basic Circuits PPT

ELECTRICAL CIRCUITS AND
COMPONENT SYMBOLS
1
Some circuit symbols
In circuit diagrams components are represented by
the following symbols;
cell
ammeter
battery
voltmeter
switch
motor
lamp
resistor
buzzer
Circuit
Breaker 2
The CELL
The cell stores chemical energy and transfers it to
electrical energy when a circuit is connected.
When two or more cells are
connected together we call this
a Battery.
The cells chemical energy is
used up pushing a current
around a circuit.
3
What is an electric current?
An electric current is the flow of electrons through
a circuit.
+
-
In which direction does the current flow?
from the Negative terminal to the Positive terminal of a
cell.
4
simple circuits
Here is a simple electric circuit. It has a cell, a
lamp and a switch.
cell
wires
switch
light
To make the circuit, these parts are connected
together with metal wires.
5
simple circuits
When the switch is closed, the circuit is complete, and
the lamp lights up. This is because there is a
continuous path for the electric current to flow
around.
If there were any breaks in the circuit, the current
could not flow.
6
circuit diagram
Electrical drawings are usually drawn using symbols;
cell
light
switch
wires
7
types of circuits
There are two types of electrical circuits;
SERIES CIRCUITS
PARALLEL CIRCUITS
8
SERIES CIRCUITS
The components are connected end-to-end, one
after the other.
Electrons flow in only ONE path.
If one bulb ‘blows’ it breaks the whole circuit and
all the bulbs go out.
9
PARALLEL CIRCUITS
The components are connected side by side.
The current has a choice of routes (MANY paths).
If one bulb ‘blows’ there will still be a complete circuit
to the other bulb so it stays lit.
10
All information researched on the
following web sites.
http://www.google.ca/search?q=elect
ric%20circuit&rls=com.microsoft:enca&oe=UTF8&startIndex=&startPage=1&gws_rd=
cr&um=1&ie=UTF8&hl=en&tbm=isch&source=og&sa=N
&tab=wi
http://www.technologystudent.com/e
lec1/elecex.htm
www. Teachingzone.org (Electricity
awareness course pack for teachers
produced by C2B Media LTD
11