Re: voltages etc.

[Bernard Cleyet <anngeorg@PACBELL.NET>]

A have a different take on the question of no chem. reaction until the
connection is made.  That is, no additional reaction.  When the cell is
created a reaction occurs until the cells PD is obtained, and then the
reaction stops.  It recommences when the PD is reduced by making the
connection.

BTW, how may one, pray tell,  measure a PD without a current flow?

bc

Seth T Miller wrote:

> Hello all,
>
> I have a question, actually two, that I am discussing with another
> faculty member.
>
> Part One:
> Take a 6 volt dry cell battery.  My colleague opines that one cannot
> speak rightly of a voltage existing between the two sides of the battery
> until the terminals are connected, thus completing the circuit.  Her
> reasoning is that the chemical reaction is the source of the voltage and
> does not occur unless the terminals are connected in a circuit (except
> perhaps in very small amounts as batteries run down when left to stand).
>
> Is this a correct analysis or can we rightfully speak of a voltage
> difference between the two sides of a battery, and if so is it 6 volts
> in this case?
>
> Part Two:
> My colleague connected the positive side of a 6 volt dry cell battery to
> a 1.5 volt light bulb, then connected the other side of the light bulb
> to the ground.  The bulb does not light.  Is there a voltage difference
> between the positive side of the battery and the ground and if so is it
> 6 volts?  Why doesn't the bulb light?
>
> Her latest theory is that as soon as one touches the positive side of
> the battery, any excess charges are immediately drained off and that
> side of the battery becomes equalized with the ground.  The chemical
> reaction is not occurring, so there is no way for a voltage difference
> between the positive terminal and the ground to be maintained, thus the
> bulb does not light.
>
> Is this a correct analysis?  How could it be analyzed in more detail?
>
> Thank you-
> -Seth Miller