Re: Impedance &c.

[Jack Uretsky <jlu@HEP.ANL.GOV>]

The conclusion is IMO correct.  The maximum energy deliverered to the load
increases indefinitely with the load.  However, the time it takes to
deliver the enerygt also increases withoug bound.  Let that be a lesson to
all: DIM BULBS BURN LONGER!
                                Regards,
                                        Jack

On Wed, 7 Jan 2004, Bob Sciamanda wrote:

> Quantitatively,
> W = VK = ERK/(r + R), which has no maximum, with increasing R.  The highest
> value approached with increasing R is W = EK. ( E is the cell EMF, assumed
> constant)
>
> Bob Sciamanda
> Physics, Edinboro Univ of PA (Em)
> http://www.velocity.net/~trebor/
> trebor@velocity.net
> ----- Original Message -----
> From: "Bob Sciamanda" <trebor@VELOCITY.NET>
> To: <PHYS-L@lists.nau.edu>
> Sent: Wednesday, January 07, 2004 10:11 AM
> Subject: Re: Impedance &c.
>
>
> > The total energy delivered is W = V I T = V K, where K is a constant (as
> the
> > load R is varied) and V is the terminal voltage (across R).
> >
> > 1) If the cell is ideal (r= 0)  then both V and K are constant as we vary
> R,
> > and so W = VK is independent of R
> >
> > 2) If the cell is non-ideal (has r>0), then if  we
> > a) lower R, I will increase, K will stay fixed, and V will decrease => W =
> > VK decreases.
> > b) increase R, I will decrease, K will stay fixed, and V will increase =>
> W
> > = VK increases.   IE., if r>0 W increases with increasing R - there is no
> > maximum.
> >
> >
> > Bob Sciamanda
> > Physics, Edinboro Univ of PA (Em)
> > http://www.velocity.net/~trebor/
> > trebor@velocity.net

--
"Don't push the river, it flows by itself"
                                Frederick Perls