Toroidal Inductor Flux Calculation

[MadelineChoate]

Summary:: A 4.3 mH toroidal inductor has 100 identical equally spaced coils. If it carries an 11.6 A current, how much magnetic flux passes through each of its coils? Express your answers in milliwebers.

4.3 mH= (Wb/A)
100= N
11.6= I
Φcoil= ?

So from my observation of another question similar, I need to divide 4.3mH by 11.6A and then multiply that answer by 100N. When I input the equation I get 37.07 mWb and my answer is wrong. What am I doing wrong?

 

[kuruman]

Hi @MadelineChoate and welcome to PF.

You should be aware by now that what works with one problem need not necessarily work with another. We cannot help you figure out why your answer is wrong without more information. Specifically, here are some things to check:
1. What was the question and solution that you patterned this solution after? What makes you so sure that it is applicable in this case?
2. What exactly did you do to get the answer that you got? Have repeated the calculation in a different way to verify ots correctness? Did you remember to convert mH to H?

 

[MadelineChoate]

The question that was similar is the one below:

A 4.50 mH toroidal inductor has 125 identical equally spaced coils.

4.5 mH = .0045 H (Wb/A)
N = 125
I = 11.5 A
φ = ? - this is what we're finding

If it carries an 11.5 A current, how much magnetic flux passes through each of its coils?

The way he solved the problem was by:
φ = (.0045 H)/(11.5 A) = 3.91*10^-4 Wb
I divided that by 125 and got 3.13*10^-6 Wb. He later wrote "I realized that I should multiply the inductance by the current and got the correct answer."

So my thought process was to take (.0043)/(11.6)= 3.707 E-4 Wb. Then (3.707 E-4)(100)= .037

 

[kuruman]

So he did not show the correct formula to be used for the calculation. Do you think that you can write the correct formula, identify what number corresponds to what symbol and then substitute the numbers. Here is a link for assistance - you need to provide the algebra. Look at the equations that say $B = \dots~$ and $L\approx\dots~$ Can you put these two together and find an expression relating the magnetic flux and the inductance? Don't forget that $\Phi=BA$.