There is a uniform thin current sheet of infinite extent in the x,y plane.(adsbygoogle = window.adsbygoogle || []).push({});

Assuming the magnetic field is only a funtion z, perpendicular to the plane and that the magnetic field direction is paralell to the plane and perpendicular to the current direction (which is in the positive x direction)

I am asked to find an equation for the magnetic field due to the current plane using the integral form of Gauss law.

Now, all we have been taught is the magnetic field due to a current in an infinatly long wire. So, what wire would simulate this plane? I am guessing one with an infinate radius. As the magnetic field from an infinatly long straight wire does not depend on the radius, i figured that the magnetic field due to the plane is zero. Is this right? I got it using the below working.

B * 2Pi * radius of point to be measured = uI

B = uI/(2Pi * radius of point)

if the radius of the wire is infinant, then the radius of the point to be measured (in z direction) must also be infinant. This would make the magnetic field reduce to zero.

Are we on the right track? If you can't understand my working, just tell me if the magnetic field due to a infinant current plane is zero or not.

Thanks,

Cummings

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Magnetic Field due to a unifrom thin current sheet of infinite extent

**Physics Forums | Science Articles, Homework Help, Discussion**