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Re: EMF



Kirchhoff's Loop Rule is the only place where I distinguish between
voltage and EMF. The H&R texts used both terms (in the old days?) and
I would ask the students WHY both terms were used.
It's not 'easy' to apply K's Loop Rule to induced 'EMF's".

What are the appropriate adjectives to attach in the case of K's Loop Rule?

At 8:00 PM -0500 on 3/23/02, John S. Denker wrote
Ludwik Kowalski wrote:

Referring to the EMF my textbook states that the use of the
term electromotive force "is discouraged." We know why.
So what is the alternative?

What's wrong with "voltage"?
That's what I've always used.

Sometimes people apply the term EMF to a particular
type of voltage, to distinguish it from other
voltages in the problem. But in each case a more
descriptive term usually suggests itself. But it's
still a voltage, with appropriate adjectives attached.

In quite a few cases it makes sense to speak of the
Thévenin-equivalent open-circuit voltage, denoted
Vth or Voc. This solves the EMF problem for batteries
and motor/generators.

If there are other cases remaining unsolved, please
elaborate.

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