A tightly wound toroid of inner radius 1.2 cm and outer radius 2.4 cm has 960 turns of wire and carries a current of 2.5 A. Requried:
a. What is the magnetic field at a distance of 0.9 cm from the center?
b. What is the field 1.2 cm from the center?

a

b

Explanation:

From the question we are told that

   The inner radius is

   The  outer radius is  

    The nu umber of turns is  

    The current it is carrying is  

Generally the magnetic field is mathematically represented as

Where   is the permeability of free space with a constant value    

And the given distance where the magnetic field is felt is  r =  0.9 cm  =  0.009 m

Now  substituting values

    Fro the second question the distance of the position considered from the center is  r =  1.2 cm  =  0.012 m

So the  magnetic field is