A zero current circuit

[Samm]

Now I remember distinctly that one of my science teachers described to me a circuit that one could use to measure the potential difference of a galvanic cell; it's E₀ value, ie. it's electric potential where there is no current. It involved a transformer, a micro-ammeter, the galvanic cell and a rheostat. I want to know how it works and possibly get more info on the subject.

 

Cheers.

[John Cuthber]

This sort of thing?

http://en.wikipedia.org/wiki/Potentiometer_(measuring_instrument)

I can't see the point of a transformer- they only work with AC and a cell like that will never produce AC.

Edited December 21, 2011 by John Cuthber

[TonyMcC]

Now I remember distinctly that one of my science teachers described to me a circuit that one could use to measure the potential difference of a galvanic cell; it's E₀ value, ie. it's electric potential where there is no current. It involved a transformer, a micro-ammeter, the galvanic cell and a rheostat. I want to know how it works and possibly get more info on the subject.

 

Cheers.

I think you mean an adaptation of the circuit shown. The potentiometer would be replaced by two resistors, one fixed and the other a rheostat. I agree that there is no point in includind a transformer in a purely dc circuit.

Edited December 21, 2011 by TonyMcC

[Samm]

About the transformer, I meant a power source which, while DC, could have its voltage changed. Sorry for the confusion.

 

And yes, the pentiometer seems to fit exactly with what I remember about the circuit design.

Edited December 24, 2011 by Samm