Answer:
Polarity
Step-by-step explanation:
Magnetism is caused by the motion of electric charges. Each atom has electrons, particles that carry electric charges.
A magnetic field is characterized by poles called north and south. Magnetic polarity refers to the orientation of these poles in space.
If both voltages have the same polarity, the signal is called unipolar; if the voltages have opposite polarity, the signal is called bipolar.
The polarity of a magnet actually can be reversed, but the process can take several tries before it is finally successful. In order to reverse the polarity of a regular magnet, you need the power of a battery and a coil of copper.