2 • Capacitors

Define Capacitor

Any arrangement which allows the potential of a conductor to be reduced without removing charge from it

What type of capacitor is this?

Parallel Plate Capacitor

List the factors on which the capacitance of a capacitor depends

• Distance of separation

• Overlap area

• The dielectric

Label This Formula

Parallel Plate Capacitor

C - capacitance

E - permittivity

A - area

d - distance

What page of the log tables can you find the Parallel Plate Capacitor Formula?

62

Demonstrate an experiment to show the distance of separation between parallel plate capacitors • 1

• Charge plates by voltage

• Bring Y closer to X

Demonstrate an experiment to show the distance of separation between parallel plate capacitors • 2

• Divergence decreases

• Potential of X decreases

Demonstrate an experiment to show the distance of separation between parallel plate capacitors • 3

• Divergence increases the capacitance

• As distance decreases, capacitance increases

Demonstrate an experiment to show the overlap area between parallel plate capacitors • 1

• Charge plates by voltage

• Plates at a fixed distance

Demonstrate an experiment to show the overlap area between parallel plate capacitors • 2

• Move Y to one side

• Divergence of GLE increases

Demonstrate an experiment to show the overlap area between parallel plate capacitors • 3

• Potential of X is increasing

• As Area decreases, capacitance decreases

Demonstrate an experiment to show the dielectric between parallel plate capacitors • 1

• GLE indicates potential on plate X

• Put polythene block in between plates

Demonstrate an experiment to show the dielectric between parallel plate capacitors • 2

• Divergence decreases

• Potential decreases

Demonstrate an experiment to show the dielectric between parallel plate capacitors • 3

• Capacitance increases

• The insulator increased the capacitance

Demonstrate that parallel plate capacitor stores energy

• Charge capacitor with a battery

• Connect capacitor to a bulb

• Bulb lights up