E&M > Electromagnetic Induction > Induced Currents DCS# 5K10.62

ROTATING COIL MAGNETOMETER

rotating coil

APPARATUS
motor-driven rotating coil 101-07-D
oscilloscope with camera
202
magnet
202-20-D5


DESCRIPTION
The amplitude of the induced emf in the motor-driven coil can be used to determine the magnitude and direction of the magnetic field of the earth (54 uT at an inclination of 69º in Oberlin) or of the big gray horseshoe magnet (0.10 T at the center of the gap).

The coils have 1000 turns on a 1" square frame.  The rotation rate is 29 Hz.
We also have a Rawson rotating coil magnetometer. 

NOTES

Make sure the contacts are clean, use a shielded cable, and connect the frame of the motor to the oscilloscope ground.