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Re: Faraday induction

"John S. Denker" wrote:
My recommended solution: I just talk about "voltage". It's easy. It
removes any temptation to talk about "EMF".

I am of the completely opposite opinion: I put "voltage" on the same
list as "heat:" useful to experts but dangerous to initiates. Consider
the following statement that will appear to you as perfectly benign:
"At this point in your circuit the voltage should be 0.7 V."

What does that really say? "There should be a 0.7 V potential
difference between this point in your circuit and some other point that
I'm not going to tell you about, so nyah, nyah."

WE know that a voltmeter has not one but two inputs, but do our
students? In teaching E&M to freshman, I've always re-written
everything replacing V by Delta-V and always being careful to call it a
potential difference instead of "voltage."

Of course, I can't call emf a potential difference. I am open to a new
name, but in the meantime I have come up with nothing better than
calling it "ee em eff" and refusing to say what the letters stand for.
I am sure that for 95% or more of students, it is not the _name_ that
confuses them.