B-field Definition and 106 Threads

Howdy I'm having a ton of trouble with this question Basically I have a spiral coil running around the z-axis with radius 'a' height '2b' and pitch 'c'. The point (x,y,z) = (a,0,0) is on the spiral and n = 2b/c (that's the number of turns on the spiral). There's a steady current running...

If there's a loop exiting a B-field, where half of it is in the b-field and half of it is out. How would a potential difference be found in the wire? I said that V = BLv, (where L is the height of the loop, disregarding the width) and found V to be 3v. Although, there is one resistor on the...

How is potential difference found between two plates in a B-field? Any help is greatly appreciated.

Can someone explain to me how a neutron star (I'm assuming that it has no charge even on the microscopic level) can have a magnetic field? And even if I assume that there is some residual charge left after the collapse, how could the magnetic poles point in significantly different direction...

Two parallel wires repel each other with a force per length of 1.00*10^-3 N/m when spaced a distance of 2.50 cm apart. If one wire has a current of 100A, what is the current in the other wire? Don't know where to start this one.

Hey! I am trying to get a rough estimate for the B-field (from a electromagnet) required to levitate a train. Assuming the train is of mass M, the force required to lift it and hold it at a distance D would have to equal M x g right? But how do i estimate the b-field an electromagnet...