Experiment Setup
Magnetization
- Wrap a steel needle with insulated wire;
- Connect the wire with power supply operating under constant current mode. A small resistor of 2Ohm is connected in serial with the coil.
Measurement
- Fix a bar magnet (in Savary’s experiment a wire is used instead of magnet) on the table, make the orientation of the magnet the same as earth magnetic field ;
- Suspend the needle in horizontal plane and put the center of needle right above the center of magnet;
- Magnetize the needle and rotate it to be perpendicular with the magnet;
- Release the needle and start timing;
- Count the time of 30 oscillations.