Solve the following problems on your own paper. Please:

• Show all work.
• Put a box around your final answer to each problem.
• Be sure proper significant figures (SF) used for all answers.
• Separate all solutions with a horizontal line on your paper.
• A random selection of five problems will be graded for 20 points each.
• Solutions for suggested odd problems can be seen by following links.
• Solutions for assigned problems will be linked from this page after the due date.

Chapter 29

#4

You can ignore the straight sections. Use equation 29-9 for the curved sections, keeping signs (directions) in mind. Problem #5 (a suggested problem) is similar.

#8

This is similar in principle to Chapter 22, #8, one of the first problems we studied.

#12

For part (a), write an expression for the net magnetic field as a function of x, then differentiate and set equal to zero, etc.

#28

If it helps, you can solve for the force on L = 1.00 meters of wire. That is identical to solving for force per meter.

#30

This problem involves two-dimensional vector addition. Be careful with signs when combining components at the end.

#32

First, find the distance between wires 1 and 2 using the case when the net force is equal to zero. Then use the asymptotic case to find the value of the current in wire 2.

#42

Find N, then multiply by the circumference (2*pi*r) of one loop.

#48

The generalized formula for the magnetic field at the center of a loop is equation 29-10, a simplification of equation 29-26 with z = 0.

Suggested problems from chapter 29:

1, 2, 3, 5, 6, 7, 9, 11, 15, 21, 22, 27, 29, 31, 33, 34, 35, 37, 40, 41, 43, 44, 45, 46, 47, 49, 50, 51, 59, 65, 66, 68, 70, 74, 77, 78, 79

Chapter 30

#2

Sample problem 30-2 is similar.

#14

If you integrate I = EMF/Resistance, you get Q = Delta(Flux)/Resistance. The angle between the axis of the coil and the magnetic field is 20 degrees, not 70 degrees. Problem #13 is similar to this one.

#26

Find the induced EMF. For this kind of problem we use the equation for power: P = EMF^2/Resistance. Then Energy = Power * time.

#34

Rather than trying to integrate along some arbitrary path, instead just find the - d(Flux)/dt, which is this case is just A*dB/dt.

#42

See figure 30-17 and associated text on page 806 for help on this one.

#48

This is very similar to RC problems we did previously.

Suggested problems for chapter 30:

1, 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 16, 17, 20, 21, 27, 29, 30, 31, 35, 37, 38, 39, 43, 44, 45, 46, 47, 49, 50, 51, 52, 53, 54, 55, 58, 74, 75, 83, 84