# Homework Help: H of a toroidal coil with relative permeability

1. Dec 7, 2008

### FUT7CAP

Consider a toroidal coil of rectangular section of N turns, for every one of which circulates a stream I. The inner radius of the coil is a and b is the exterior and the height is h. The core of this coil is a material inhomogeneous in such a way that their magnetic permeability just depends on the angle theta in this way

$$\mu o=(1+k cos\theta)\mu$$

vector magnetic field H ???

Thanks,
José

Last edited: Dec 7, 2008
2. Dec 10, 2008

### FUT7CAP

Well, I know

H must be variable because $$\mu$$ is variable.

H=B/$$\mu$$

So B is variable but B also depends of $$\mu$$ and r

For me B is:

B=($$\mu$$*I*N)/(2$$\pi$$r)

so

H= (I*N)/(2$$\pi$$r)

This mean that H dont depend of the center material of toroid

Last edited: Dec 10, 2008
3. Apr 19, 2011

### Psylock7

Actually, for a toroid, B= (u0*ui*N*i)/(2PIr)*[ln(rb/ra)] which makes me think that H is really H= N*i/2PI(rb-ra)

I'm trying to figure this out too.