Electromagnets

Series Circuit

0

voltmeter

+

NO

0

currentmeter

Two light bulbs in series with an push button and a current meter.

A push button in the open position.

Series Circuit

+

0

currentmeter

NO

0

voltmeter

A push button in the closed position.

Series Circuit

0

voltmeter

+

NO

0

currentmeter

A push button in the open position.

Series Circuit

0

voltmeter

+

NO

0

currentmeter

A push button in the open position.

Inductor with a ferromagnetic core

light bulb with an incandescent filament

Series Circuit

+

0

currentmeter

NO

0

voltmeter

A push button in the closed position.

Magnetic field lines indicate presence of a magnetic field

When current flows a magnetic field is generated around the flowing electrons.

Note:(a) This magnetic field is also called an electromagnetic field. (b) This magnetic field is the same magnetic field as the field made by a horse shoe magnet

Normally Open Relay Circuit

+

0

currentmeter

Flexible thin metal (magnetic) sheet.

Wooden Sounding box

Wooden block(noise will be

made when block hits sounding board)

0

voltmeter

NO

Series Circuit

+

0

currentmeter

NO

A push button in the closed position.

When current flows a magnetic field is generated around the flowing electrons.

0

voltmeter

Normally Open Relay Circuit

+

0

currentmeter

0

voltmeter

NO

Normally Open Relay Circuit

+

0

currentmeter

0

voltmeter

NO

+

Series Circuit

0

currentmeter

NO

A push button in the closed position.

When more current flows a stronger magnetic field is generated around the flowing electrons.

+

0

voltmeter

+

Normally Open Relay Circuit

+

0

currentmeter

0

voltmeter

NO

+

MathThe voltage value times the current value equal the power

Power of electric current is directly proportional to the magnetic field strength.

B is the symbol for field strength

B can have units of Newton per cm

VocabularyInductor

Voltage - measured in volts

Current- measured in Amperes

Power- measured in volt-Amperes

Note 1 Watt equals 1 volt-Ampere

End of Presentation