[Phys-L] closed loop superconductor circuit with current in vaccum

[Diego Saravia <dsa@unsa.edu.ar>]

> the only magnetic field is the produced by the current.
>
> Is there any simple way to study what happens when you change the area of
> that loop?

The flux trapped by a conducting loop is constant.

This is an extreme example of Lenz's Law, which is itself a direct
corollary of the Maxwell equation:
    Voltage = flux dot
If the voltage around the loop is zero, the flux is constant.
Nice and simple.

Thank you very much

I dont understand the following

in a loop B= u I / (2r)

so flux = B Pi r2 = u Pi I r /2

if flux is constant current will grow whem you reduce the size  of the loop
(you must do work for that)

if your fem is cero why will the current grow ? The same number of
electrons runing in smaller space?



-- 
Diego Saravia
Diego.Saravia@gmail.com
NO FUNCIONA->dsa@unsa.edu.ar