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 four problems will be graded for 25 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 21

#2

Power is calculated using rms values, not max values.

#8

This problem asks for max current, not rms current.

#10

Be sure to explain your answer for part (d).

#14

Use equations from section 21.3 for this problem.

#24

Recall that the voltage drop across the inductor (also called "induced emf" or "back emf") depends on DI/Dt, the rate of change of current, or the slope of the current vs time graph. When current is maximized, what is the slope of the current vs time graph? Recall: when is the slope value largest on the current vs time graph? There is similar logic on problem #30.

#36

The loop rule only applies to instantaneous voltages, never to rms voltages, which are averaged over a time cycle.

#42

When the frequency changes, the inductive reactance, capacitive reactance and the impedance all must be recalculated from scratch.

#46

The 2nd coil has the lower voltage associated with it and therefore a higher current. Both coils have the same power.

#48

Use I^2*R for power loss. I*DV only works if you use DV along the power line (which we do not know). We only know DV between the power lines.

Suggested problems from chapter 21:

C1, C4a C4b, C5, C6, C7, C8, C9, C12, C13, C14, C15, #1a #1b, #3, #4, #5, #6a #6b, #7, #9, #11, #12, #13, #15, #16a #16b, #17, #18, #19, #20, #21, #22a #22b, #23, #26, #27, #28, #30, #31, #33, #34, #35, #37, #38a #38b, #39, #40, #43, #44a #44b, #45, #47, #59, #60, #61, #62, #69a #69b, #70, #71