Hello,
I was reading/studying the transmission line chapter in the allaboutcircuits online book. Very interesting and good explanation!
DC circuits: In DC circuit, it was mentioned that we can arbitrarily choose ANY point in the circuit and assign to it the value 0V. The reference point belongs to a conductor and all other points on that same conductor will also have 0V since the conductor is equipotential.. So we pick a reference point but in reality the entire conductor becomes the reference....I think that is correct...
AC circuits: In low frequency AC circuit, this approach still works since a conductor can still be approximately taken to be equipotential (all points belonging to the conductor are at the same electric potential V). Transmission line theory is required when we are dealing with high frequency AC circuits and the circuits dimensions/lengths are comparable with the signal's wavelength. the simplest transmission line is the two parallel wire line.
Here my question: there is potential difference between any pair of points facing each other on the two different wires BUT there is also a potential difference between different points on the same wire! Even on the same wire, different points have different electric potential. Each of the wires is not equipotential...
That said, do we still pick an arbitrary point to be the 0V reference point? Or is there an optimal choice for the reference 0V point in that case?
Thank you,
I was reading/studying the transmission line chapter in the allaboutcircuits online book. Very interesting and good explanation!
DC circuits: In DC circuit, it was mentioned that we can arbitrarily choose ANY point in the circuit and assign to it the value 0V. The reference point belongs to a conductor and all other points on that same conductor will also have 0V since the conductor is equipotential.. So we pick a reference point but in reality the entire conductor becomes the reference....I think that is correct...
AC circuits: In low frequency AC circuit, this approach still works since a conductor can still be approximately taken to be equipotential (all points belonging to the conductor are at the same electric potential V). Transmission line theory is required when we are dealing with high frequency AC circuits and the circuits dimensions/lengths are comparable with the signal's wavelength. the simplest transmission line is the two parallel wire line.
Here my question: there is potential difference between any pair of points facing each other on the two different wires BUT there is also a potential difference between different points on the same wire! Even on the same wire, different points have different electric potential. Each of the wires is not equipotential...
That said, do we still pick an arbitrary point to be the 0V reference point? Or is there an optimal choice for the reference 0V point in that case?
Thank you,