Skip Ribbon Commands
Skip to main content

5H25.15 - Rotating Magnetic Field

The Web Part cannot find an InfoPath form in the specified location. Either the location does not have an InfoPath form associated with it or it is on a different site collection. Modify the Web Part Properties and select a list or library on the current site.

​5H25.15 - Rotating Magnetic Field

Title5H25.15 - Rotating Magnetic Field

To demonstrate what happens to a perminant magnet that is suspended in a rotating magnetic field​.

Assembly Instructions

Connect one set of coils to channel 1 output of the amplifier.  Connect the other set of coils to the channel 2 output of the amplifier.  2 sodium bulbs are connected in series with the coils to limit the current and provide enough impedance for the amplifier.  The 2 inputs are connected to 2 different function generators to allow each coil to be controlled separately.  Set up a camera on the hanging magnet so the audience can view what is going on inside the coil assembly.

Setup Time7
Operation Time5
Preview Time10
Operation Instructions

Set each function generator to the same value of about 3.1 Hz.  Turn on the amplifer and ramp up the amplitude until both sides illuminate the first yellow bar of the power indicator.  ​To get the magnet to begin to spin, the function generators must be adjusted slightly to one another until the phase is correct.  Once that occurs, the magnet will begin to spin.  Sometimes it spins continuously and sometimes it will pulse as it is rotating.

Demo on DimeNo
PIRA 200No
Export Instructions (if different)
HazardsMagnets - Strong Magnets Present, Fragile: Caution when Transporting
Category5 Electricity and Magnetism
Subcategory5H - Magnetic Fields and Forces
Keywordsrotating, magnetic, field, phase, shift
Construction Information
rotating magnetic field assembly - 4 coils with 2 parallel crossing each other, suspended permenant magnet
amplifier - Samson Servo 120A
function generator
banana cable
cable RCA to banana
camera - b&w