First, we taped the mirror to the magnet.
Then we tied it on a string and lowered it into a glass full of water
After that, we pointed a laser ray in to the mirror which projected the laser ray on a measurement “screen”
The screen showed the angle of the deflection
The result of the simple compass should not change unless there is a disturbance in the magnetic field – metal objects or another magnet.
Breadboard powering the electromagnet.
Magnetometer with the Helmholtz coil.