Calculating Magnetic Field of a Toroid Using Ampere's Law

[snipaj9696]

Use ampere's law to determine the magnetic field (a) inside and (b) outside a toroid, which is like a solenoid bent into the shape of a circle.

Here is my work..

IS MY WORK CORRECT?

a.) B(2PIr)=MoIenc

and I found that B=MoNI/2pir


b.) the magnetic field is 0 outside the loop

 

[Hootenanny]

Yes, you are correct.

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