Transcript Electricity #2

ELECTRICITY
Circuits
What are
they?
• Circuits are a
path along
which
electricity
moves
Closed, series circuit
Kinds of Circuits
Open
Closed
These circuits do not have
These circuits have a
a complete path to follow. complete path to follow.
The power cannot pass
There are no openings in
from the source to the
the path.
receiver.
Light when it is turned off
Light when it is turned
on
Kinds of Circuits
Series
Parallel
These circuits have These circuits have more than
only one path for
one path for electricity to flow
current to flow.
through.
If one light goes out If one light goes out the rest
they all go out
stay on
Old Christmas Lights
*Your house
*Power lines
Series Circuits
Parallel Circuits
Voltage
• Voltage is defined as the amount
of work done or the energy
required in moving a unit of
positive charge (1 coulomb) from
a lower potential to a higher
potential. Voltage is also called
potential difference (PD).
Current
• Current is the amount of electric
charge (coulombs) flowing past a
specific point in a conductor over an
interval of one second.
1 ampere = 1 coulomb/second
= 6.24 x 1018 electrons
• Electron flow is from a lower potential
(voltage) to a higher potential (voltage).
+
e
e
e
Wire
e
-
Resistance
Resistance
•Charges passing through any
conducting medium collide with
the material at an extremely high
rate and, thus, experience friction.
Resistance
•The rate at which energy is lost
depends on the wire thickness
(area), length and physical
parameters like density and
temperature as reflected through the
resistively
Ohm’s Law
Georg Ohm
• There is a simple linear relationship
between voltage, current and
resistance.
V  IR
Electricity
Know what it is
Know the
different kinds
Know about the
different kinds
of circuits
Know about
conductors and
insulators
ElectroBoard
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Unfold and write the first matching column on
the left hand side.
On the right hand side, write the second
matching column.
Place a brad in the first hole on the left side.
Locate the correct answer on the right side and
place a brad in that hole.
Connect the brads with a strip of aluminum foil.
Tape the ENTIRE strip of foil down between each
item!
9. This creates a series circuit that you can use
for review. All you need to test the item is a
continuity tester or a series circuit setup.
SOLAR POWER