# How to derive the curl of E equation in the frame of the conductor?

1. Jun 12, 2014

According to wikipedia, "The moving magnet and conductor problem", I stopped at the equation shown in the attachment.
It said that the curl of the E ( electric field in the frame of the conductor) is equal to minus of the dot product of the velocity of the conductor and the del multiplied by the magnetic field.

How to derive this formula?

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2. Jun 13, 2014

### UltrafastPED

3. Jun 14, 2014

But i have 3 concerns:
1) The above equation should equal to ∇B(x') ∂vt/∂t not to the composite ∇B(x') ° ∂vt/∂t
2) How (v°∇)B is driven from ∇B(x') ° v?
3) In wikipedia, it is a dot product (v.∇) B not a composite function (v°∇)B

Last edited: Jun 14, 2014
4. Jun 14, 2014

∂B(x)/∂t = ∂B(x+vt)/∂t

∂B/∂t= (∂B/∂x).(∂x/∂t) given that x=x`+vt

but ∂x/∂t= v

so ∂B/∂t= (∂B/∂x). v

5. Jun 14, 2014

### UltrafastPED

Yeah, a dot not a composition. Couldn't find the dot in the menu. Gotta learn LaTex someday I keep saying to myself!

6. Jun 14, 2014