# Common problems

Electric Machinery – Fall 2008

## Common problems

### Problem Set 3

• Here is a matlab example that will help with problem 1.

### Problem Set 2

• In problem 1, part c you are given the following expression for the self inductance of coil 1: L_{11}(theta) = L_{01} + L_{11}cos(2*theta). In that expression, L_{01} and L_{11} are simply two constants.
• In problem 1, part e you are given the following expression for the mutual inductance: M(theta) = Mcos(theta). Once again, M is simply a constant.
• Similarly, the expression for the self inductance of coil 2 that is found in problem 1 part f also has two constants, namely L_{02} and L_{12}.

### Problem Set 1

• Remember that the solenoid in problem 1 has a cylindrical shape. This should help you decide whether or not the magnetic circuit has multiple loops.
• You should read sections 1.1-1.4, 3.1-3.6 in Fitzgerald and Kingsley.
• You may find it difficult to finish either problem 1 or problem 2 until after the first lecture. You should, however, be able to start both problems.