00:05
Right, so this is question 28 .54, where we have a solenoid that's a torus, and we know that the current in the windings is 2 .4 amps.
00:17
We know the number of windings.
00:18
We know the mean radius, which i've converted here to meters.
00:21
And we know that the magnetic field inside the windings is 1 .94 tesla.
00:28
We also know that now there's some magnetic material inside of the solenoid, and we want to figure out the magnetic.
00:35
The magnetic susceptibility and the relative permeability of the material that fills the solenoid.
00:43
So this is our normal equation for the magnetic field inside of a toroidal solenoid without any magnetic material inside.
00:53
So the only difference that we have now is that we need to replace our mu not here, that's the permeability of free space, with km times mu not, because we now have this factor of this extra permeability due to this additional magnetic material.
01:10
So for part a, we're just asked to solve for km.
01:15
So we can just rearrange this equation so that it's solved for km...