(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

B = variable magnetic field, of constant direction (e.g B = b cos(wt) N, where N=const vect)

A = magnetic potential vector of B

R = vector from some origin O to a point M

It is assumed that no exterior electric potential is present.

Problem: to find the electric field E at M caused by the variable magnetic field.

2. Relevant equations

A=1/2 B x R (A depends on the origin O, but this is OK since the magnetic potential vector is not uniquely determined).

E = -dA/dt (Maxwell-Faraday, since there no exterior electric potential is present)

It follows immediately that E = 1/2 dB/dt x R, but then, the electric field depends on the position of the origin O, an absurdity since the electric field is uniquely defined.

What's wrong?

3. The attempt at a solution

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Electrodynamics - I'm trapped in a stupid paradox - pleas help

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