Understanding Buzzing Sounds from Power Lines and Transformers

What is the typical frequency of the buzzing sound produced by power lines and transformers?

• 90 or 100 Hertz

• 50 or 60 Hertz

• 30 or 40 Hertz

• 70 or 80 Hertz

What causes the internal accessories of a transformer to vibrate?

• Sound waves

• Magnetic fields

• Electric current

• Heat

What is magnetostriction?

• A phenomenon where ferromagnetic materials expand and contract

• A method to reduce transformer noise

• A process where magnetic fields cause sound

• A type of electrical discharge

What phenomenon causes the buzzing sound from overhead power lines?

• Magnetic resonance

• Electric hum

• Corona discharge

• Magnetostriction

What additional effect does corona discharge produce besides a buzzing sound?

• A loud bang

• A bluish glow

• A strong vibration

• A bright flash of light