Filename: Magnetic Domains:  Barkhausen Effect

Electricity and Magnetism

Name: Barkhausen Effect

Location:  L314

Equipment:  3200 turn coil with sound cable attached, strong magnet, ferromagnetic steel, high gain audio amplifier (guitar amp).

Procedure: A 3200 turn coil is connected to a high gain amplifier (guitar amp works great!). A piece of ferromagnetic steel is placed inside the coil. Firmly hold the piece of steal and bring the strong magnet close to the steel.  A noise will be heard from the amplifier as the domains inside the steel align with the magnetic field. (NOTE: Picture has an error!!!  The cable from the coil should be plugged into the guitar amp input on the left!!)