It is AC, it doesn't have a polarity!
With AC first one wire is positive and the other is negative, the in a 60th of a second (or so ) this is reversed. The change over from one state to the next is normally a smooth sinusoid.
It is AC, it doesn't have a polarity!
With AC first one wire is positive and the other is negative, the in a 60th of a second (or so ) this is reversed. The change over from one state to the next is normally a smooth sinusoid.