Transcript SNC1D0 Electric Circuits

Current Electricity
What is Electric Current?
• Electric current is the flow of electricity
through a conductor.
• Current is described as the movement of
electrons.
• An electric current can provide energy to
do work
– Example: Turn on a light, move a motor.
ELECTRICAL CIRCUITS
CELLS
How can we get a current of electricity?
A cell stores chemical energy and changes it to
electrical energy when a circuit is connected.
When two or more cells are
connected together it is called a
Battery.
The cell's chemical energy is
used up pushing electric
current.
What is an electric circuit?
Electrons flow in a complete path from one end of a
cell, through conducting wires, to the other end of a
cell.
+
-
In which direction does the current flow?
Current flows from the Negative end of the cell (terminal)
to the Positive terminal of a cell.
Simple Circuits
Here is a simple electric circuit. It has a cell, a
lamp and a switch.
cell
- +
switch
wires
lamp
To make the circuit, these components are connected
together with metal connecting wires.
When the switch is closed, the lamp lights up. This is
because there is a continuous path of metal for the
electric current to flow around.
- +
If there were any breaks in the circuit, the
current could not flow.
Circuit Diagrams
Scientists usually draw electric circuits using symbols;
+
- +
+
cell
lamp
switch
wires
More Circuit Symbols…
There are many types of symbols you can use for
drawing circuit diagrams;
cell
ammeter
battery
voltmeter
switch
motor
lamp
resistor