Transcript c,v, r and conductors insulators

Current, Voltage & Resistance
Conductors & Insulators
1
Energy in a Circuit...
is similar to water through pipes
We will learn how to measure the energy in a circuit
and how...
and
are related.
2
is a measure of “potential difference.”
The unit for voltage is volts (V)
Potential Energy
(height)
1.5 V
Potential Difference
1.5 Meters
0.0 V
To Lower Energy
The potential difference
(voltage) is 1.5 V. 3
The higher the energy, the greater the
voltage (potential difference).
Higher Potential
energy (height)
Greater
Potential Difference
3.0 V
3.0 Meters
0.0 V
To Lower Energy
The potential difference
(voltage) is 3.0 V. 4
= 1.5 volts
3.0V
?V
Is the voltage the same in A, C and D cell batteries?
Let’s look.
5
is the rate that the electricity moves.
How fast (speed) is
the electricity flowing
through these wires?
CURRENT (I) is measured in Amperes (Amps).
How fast is this water coming out?
+
6
Direct Current (DC)
Flows in 1 direction
Only Batteries –
AAA, AA, C, D Cell
These are all 1.5V each, but
the difference in size means
they should last longer
period of time.
Alternating Current (AC)
Flows 2 directions
Current goes back and forth
about 60 times per second.
Example: Wall socket is 120v
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is anything that opposes the flow of electrons or
prevents electricity from moving.
Measured in units called Ohms (  ).
Back to the water analogy…Which of the pipes below would
prevent water from traveling the fastest?
Pipe 1: Smaller Diameter Pipe
Pipe 2: Larger Diameter Pipe
The smaller pipe would have greater resistance to the
flow because it has a smaller diameter and not as much
water goes through it.
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Which of the following do you think
would be most resistant to
electrical current? Why?
Rubber
Glass
Plastic
These materials DON’T allow current to move easily
through them.
They have a strong resistance to the flow of electrical
current.
Therefore they are called
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Which of the following do you think
would be the least resistant to
electrical current? Why?
Rubber
Glass
Plastic
These materials allow electrical charge (current) to
move easily through them.
They have little resistance to the flow of electrical current.
Therefore they are called
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Match the word on the left to the phrase on the right.
Resistance
(R) in Ohms
How Fast?

Current
How much?
(I) in Amps
Voltage
(V) in Volts
How much is it slowed
down?
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