Spice modelling of back EMF

Pofential has all the wrong symmetries for being a force.

For instance:

1. Potential is a relative measure. It's defined as the integral of E dot d s over some arbitrary path joining two points. In the absence of time-varyi ng B fields, it's independent of the path chosen. Thus you can add a consta nt to the potential everywhere without changing the fields, i.e. without af fecting the operation of circuits.

A circuit inside a continuous metal shield won't even notice if you put it on top of a van de Graaf generator at 400 kV.

If voltage were a force, things would get interesting in there. ;)

1. Voltage is a scalar, whereas force is a vector. That is, force has a dir ection, and voltage doesn't. If I increase the voltage on the above shield can, which direction would that push the electrons inside?

Cheers

Phil Hobbs

V = I*R, therefore voltage equals current.

You're getting worse, if that's possible.

Do you think that voltage is force?

Dimensional analysis can be used in the forward direction to suggest design. If you do want to have a voltage create a force, you can look at all the correct dimensional units and decide what hardware you'll need.

Force = f(volts, xxx, yyy...) tells you that you need some xxxs and yyys to do the job. If you get the units right.

It's really more of a *pressure* but I imagine you'll pick an argument with that, too.

So it's not measured in Newtons, it's measured in Pascals?

We use "volts", which seem to work.

Your statements may be correct, but how can you Hex-Plain the Aharonov-Bohm Effect? Quantum witchery?

But some are more equal than others...

Essentially unrelated. The A-B effect is a phase shift of the wave function of an electron, caused by the magnetic 'vector potential' A. It requires a n electron interferometer to measure. It doesn't change the electric potent ial.

Vector potentials have more complicated symmetry properties than scalar one s, but they're covered in undergraduate E&M, so it's nothing too spooky at all.

Cheers

Phil Hobbs