Help with homework please :-)

Thread Starter


Joined Dec 20, 2006

I have done most of it and am only really looking for confirmation that it is right.

So heres the question and answers I have gotten. Please could someone check these for me to confrim thay are the right answers.

Thank you :)


A magnetic core (shown below) is made with a material which has a relative permeability of 2400. the coil has 2400 turns and a current of 2A is flowing through the coil. the core has a cross-sectional area of 2cmX2cm.
The permeability of free space is u0=4pi X 10^-7 Wb/Am

i)Draw the magnetic circuit
ii) Determine the reluctance of each section of the core.
iii) determine the flux in eacch leg of the magnetic core flux1, flux2, flux3.
iv) If two air gaps having a length of 0.5cm each are cut in the middle and right hand legs of the core, draw the new magnetic circuit and determine the flux in each leg of the magnetic core flux1, flux2, flux3.
v) Compare the flux values found with and without the air gaps.
vi)Repeat (i) to (v) if the coil is now placed in the middle leg.

The Image is attached to this post.

My results:

i) See attached RESULT ONE PIC
ii) S=6963 At.Wb^-1b^-1
iii) Flux2=1.34, Flux3=1.005, Flux1=2.3457

Rest to be completed

I hope to hear from you soon,


P.S Please only send the final answers not the working as im only looking to check that what Ive done is right.



Joined Jan 1, 2007
just a quick question aswell as i have had a simular question set, how do you determine how many resistors there are and if they are in parrallel or series, once converting from magnetic. thank you