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Just a few questions:

1)What is flowing through the wire?

2)What function does the battery have?

3)Is this animation an accurate depiction of the behavior of the electrons in the circuit?

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Just a couple of questions:

1)Will the charges build up on the plates FOREVER?

2)When will the charges stop flowing?

3)Why don’t the charges jump from one plate to the other?

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Just one question:

1)What will happen to a light bulb if we include it in the circuit?

Ratin

g C

ap

acito

rs

•Capacitance–The ratio of stored charge to the electric potential difference

Q α VQ = VC

Charge(Coulombs

- C)Potential DifferenceVolts (V)

Capacitance(Farads -

F)

Ratin

g C

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acito

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•Capacitance–Also determined by the construction of the capacitors•Area of plates (A)•Distance between plates (d)•Type of insulator between plates (r)–Plastic, glass, ceramic, paper

C =

or

Ad

Ele

ctric Pote

ntia

l En

erg

y

• In A Charged Capacitor

•PE = ½ (charge on one plate) (final potential difference)

•PE = ½ Q V

Summary of Variables & Units

Q Charge C

V Voltage (Electric

Potential)

V

C Capacitance F

PEC Potential Energy

J

E Electric Field

N/C22 Q

PE = ½ Q V = ½ C V = 2C

Where

AR

E T

HEY?!

• Prevent information loss– Supplies power while battery

charges• Car audio for amplifier

– Stores energy for demand• Pulsed lasers

– High energy, short time lasers• Weapon detonators

– nukes• Flashes in cameras

– Listen to them whine• Keyboards

– Changes distance between plates• Fuel level detection in airplanes

– Changes properties of insulator (fuel)