# Magnetic susceptibility measurement

1. Jun 22, 2010

### geetika

Hi,

I have to make a coil.I do not know anything about its dimensions but know that it is to be used to measure magnetic field,its actually to be used in a magnetic susceptibility measurement.There are 3 coils, drive, excitation, measurement and I/p is given at 1000hz frequency.
I need to know the No. of turns ?Please suggest!"

2. Jun 27, 2010

### geetika

Coils

I have to wind 3 coils,The transmitter/drive/excitation and the reference coils are wound one over the other on the solenoid and the receiver/measurement is 40cm down this.Ref and msmt coils are in the maxwell's inductance bridge.In order to consider the number of turns(N),initially when I am just driving the DRIVE/EXCITATION/transmitter COIL, do I still need to consider the number of turns of the Reference coil- although the ref. coil is not electrically connected to drive coil circuitry.But it is just that the transmitter/drive coil and the ref are wound one over the other.I am considering the formula B=u0NI/L: B=35000nT(I have to get).U0=4*3.14*10^-7, N=I need to find,I= Current in the COIL and L= Length is the linear length of solenoid over which the coil is wound.Is this formula, that I m using correct? or Should I use,B=u0NI/A or B=U0NIA.I need your help.I am not sure about the last two formulas.In the first I am NOT SURE is it the LINEAR LENGTH or the 2piR

Last edited: Jun 27, 2010
3. Jun 27, 2010

### Staff: Mentor

Re: Coils

Well, if you are not sure about the equations, where are you getting them from? Do the dimensions work out? The dimensional check should show you which equation is more likely to be correct...