Homework Assignment 15
Due Dec. 5, 1997

1. Problem 5.19 from the text.

2. Problem 5.20 from the text.

3. Problem 5.21 from the text.

4. Consider a toroid like the one in Figure 5-18, except that the cross-section of the toroid is square -- looking at the toroid cut down the middle, you would see this:
   

   Find the self-inductance of the toroid. (Note: the field in the toroid is still given by Equation 5.50.)

5. Calculate the inductance of the toroid of Problem 4 in another way:
   1. Find the energy stored in the toroid of Problem 4 using Equation 5.106 from the text.

   2. Using Equation 5.103 from the text and the result from Part (a), find the inductance of the toroid, and show it is the same as you found in Problem 4.

6. Consider the toroid of Problem 4. Assume a secondary coil with N₂ loops is wrapped around the toroid. Find the mutual inducatance L₁₂ between the two coils.