Is neutral wire at 0 potential??
Does that mean we can easily touch it??
Take a read through the following threads:
Simple Electrical Question:
Neutral wire is usually at ground potential, but since the point at which your system is grounded (earthed) might have a different potential from the point at which you're standing, and since the neutral wire may be carrying a large return current (which means the point at which you're touching the wire may not be at earth potential), you should refrain from needlessly touching the ground wire.
And yes, when analyzing AC circuits the + and - help facilitate your analysis. Unless there's a DC offset somewhere.
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