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Question 1

A) The capacitive reactance increases by a factor of four.
B) The capacitive reactance increases by a factor of eight.
C) The capacitive reactance is unchanged.
D) The capacitive reactance decreases by a factor of eight.
E) The capacitive reactance decreases by a factor of four.

Answer 1

E) The capacitive reactance decreases by a factor of four.

Question 2

Which of the following units results when calculating the quantity …

Answer 2

Ohm

Question 3

current independent of frequency
A) resistors only
B) inductors only
C) capacitors only
D) a combination of inductors and resistors
E) a combination of inductors and capacitors

Answer 3

A) resistors only

Question 4

A battery is used to drive a circuit
Which combination of elements is most likely to comprise the circuit?
A) resistors only
B) inductors only
C) capacitors only
D) a combination of inductors and resistors
E) a combination of inductors and capacitors

Answer 4

C) capacitors only

Question 5

A)  39 
B)  110 
C)  330 
D)  660 
E)  1.0 ◊ 103 

Answer 5

D) 660 Ohms

Question 6

Which one of the following graphs illustrates how capacitive reactance varies with frequency?

Answer 6

D) Exponential down

Question 7

TABLE: What effect does –decreasing the capacitance– have on the reactance and current in this circuit?

Answer 7

E) Increases Decreases

Question 8

A)  41 µF
B)  260 µF
C)  51 mF
D)  0.10 F
E)  0.31 F

Answer 8

A) 41 µF

Question 9

A)  49.0 
B)  72.5 
C)  97.6 
D)  145 
E)  308 

Answer 9

A) 49.0 Ohms

Question 10

A)  60.0 Hz
B)  72.4 Hz
C)  85.7 Hz
D)  98.9 Hz
E)  131 Hz

Answer 10

E) 131 Hz

Question 11

A)  0.917 A
B)  0.802 A
C)  0.308 A
D)  0.621 A
E)  0.125 A

Answer 11

E) 0.125 A

Question 12

*5 PART QUESTION: 
Graph: Sinusoidal, big and little waves, 99V, 2.8A
A)  0.14 Hz
B)  7.14 Hz
C)  12.5 Hz
D)  25.0 Hz
E)  50.0 Hz

A)  49.5 V
B)  70.0 V
C)  112 V
D)  140 V
E)  170 V

A)  1.4 A
B)  2.0 A
C)  3.4 A
D)  3.9 A
E)  5.6 A

A)  20 
B)  25 
C)  30 
D)  35 
E)  40 

A)  The element is a 25- resistor.
B)  The element is a 35- resistor.
C)  The element is a 0.45-H inductor.
D)  The element is a 360-µF capacitor.
E)  The element is a 510-µF capacitor.

Answer 12

C) 12.5 Hz

B) 70.0 V

B) 2.0 A

D) 35 Ohms

D) The element is a 360-µF capacitor.

Question 13

When the frequency of an ac circuit is decreased, the current in the circuit increases.  Which combination?
A)  resistors only
B)  inductors only
C)  capacitors only
D)  capacitors and resistors
E)  inductors and capacitors

Answer 13

B) inductors only

Question 14

Which circuit elements act to oppose changes in the current in an ac circuit?
A)  resistors only
B)  capacitors only
C)  inductors only
D)  both resistors and inductors
E)  both capacitors and resistors

Answer 14

C) inductors only

Question 15

Which one of the following graphs shows how the inductive reactance varies with frequency?

Answer 15

Answer: Positive Linear Relationship

Question 16

TABLE: What effect does increasing the inductance ?

Answer 16

Increases Decreases

Question 17

when the frequency is increased to 2f?
A) The inductive reactance increases by a factor of two.
B) The inductive reactance increases by a factor of four.
C) The inductive reactance is unchanged.
D) The inductive reactance decreases by a factor of four.
E) The inductive reactance decreases by a factor of two.

Answer 17

A) The inductive reactance increases by a factor of two.

Question 18

A)  230 
B)  320 
C)  158 
D)  56 
E)  27 

Answer 18

B) 320 Ohms

Question 19

A)  0.62 A
B)  2.0 A
C)  3.2 A
D)  1.0 A
E)  14 A

Answer 19

D) 1.0 A

When 14A is an option, the answer is 1A

Question 20

DIAGRAM ANSWERS:

which phasor model inductor and ac generator?

Answer 20

Diagram with Io pointing below x-axis

Question 21

4 PART QUESTION:
Sinosoidal Graph, big and little waves 80V, 2A
A) The element is a resistor.
B) The element is a capacitor.
C) The element is an inductor.
D) The element could be a resistor or an inductor.
E) The element could be an inductor or a capacitor.

A)  0.01 Hz
B)  0.04 Hz
C)  0.09 Hz
D)  11 Hz
E)  25 Hz

A)  1.0 A
B)  1.4 A
C)  2.0 A
D)  2.8 A
E)  4.0 A

A)  20 
B)  25 
C)  40 
D)  57 
E)  80 

Answer 21

C) The element is an inductor.

E) 25 Hz

B) 1.4 A

C) 40 Ohms

Question 22

A) The current and voltage are in phase for a capacitor in an ac circuit.
B) On average, the power dissipated by a resistor in an ac circuit is zero.
C) For a resistor in an ac circuit, the current and voltage are 90∞ out of phase.
D) Inductors in an ac circuit offer little opposition to current at high frequencies.
E) When only resistance is present in an ac circuit, voltage and current are in phase.

Answer 22

E) When only resistance is present in an ac circuit, voltage and current are in phase.

Question 23

Note the following circuit elements:  (1) resistors,  (2) capacitors, and (3) inductors.  Which of these elements uses no energy, on average, in an ac circuit?
A)  1 only
B)  2 only
C)  3 only
D)  both 2 and 3
E)  both 1 and 3

Answer 23

D) both 2 and 3

Question 24

A) The impedance is dominated by the capacitance at low frequencies.
B) The impedance is dominated by the resistance at high frequencies.
C) The impedance depends only on the values of C and L.
D) The impedance depends only on the resistance.
E) The impedance is independent of frequency.

Answer 24

A) The impedance is dominated by the capacitance at low frequencies.

Question 25

When the frequency of an ac circuit is increased at constant voltage, the current increases and then decreases. Which combination A) resistors only B) inductors only C) capacitors only D) a combination of inductors and resistors E) a combination of inductors and capacitors

Answer 25

E) a combination of inductors and capacitors

Question 26

33. For which one of the following circuit arrangements will the power factor be non-zero? A) a capacitor in series with an ac generator B) an inductor in series with an ac generator C) two capacitors in series with an ac generator D) a capacitor and resistor in series with an ac generator E) a capacitor and inductor in series with an ac generator

Answer 26

D) a capacitor and resistor in series with an ac generator

Question 27

CHART: In which circuit will the voltage lead the current?

Answer 27

D) 150  79  212 

Question 28

GRAPH: at what frequency is the largest contribution?

Answer 28

A) f1

Question 29

36. Complete the following statement: When the current in an oscillating LC circuit is zero, A) the charge on the capacitor is zero. B) the energy in the electric field is maximum. C) the energy in the magnetic field is a maximum. D) the charge is moving through the inductor. E) the energy is equally shared between the electric and magnetic fields.

Answer 29

B) the energy in the electric field is maximum.

Question 30

``` Phase Angle: A) 0∞ B) 90∞ C) 180∞ D) 270∞ E) 360∞ ```

Answer 30

C) 180∞

Question 31

Which circuit will have a negative phase angle?

Answer 31

E) 148  219  180 

Question 32

``` RCL circuit, power of +1.00. Inductance? A) 0.86 H B) 1.4 H C) 2.3 H D) 57 H E) 320 H ```

Answer 32

B) 1.4 H

Question 33

``` DIAGRAM: 60Hz, .035 H, 150 Ohms A) 300  B) 500  C) 1500  D) 1700  E) 1900  ``` ``` Phase Angle: A) zero degrees B) +5.3∞ C) ñ9.6∞ D) ñ84∞ E) +90∞ ```

Answer 33

C) 1500 Ohms D) ñ84∞

Question 34

``` A) 190 W B) 28.9 W C) 19.7 W D) 4.18 W E) zero watts ```

Answer 34

B) 28.9 W

Question 35

``` *7 PART QUESTION: 150V at 60Hz, 35 mH inductor, 85 Ohm resistor: A) 220 V B) 110 V C) 82 V D) 75 V E) 53 V ``` ``` A) 59  B) 85  C) 99  D) 120  E) 310  ``` ``` A) 13  B) 23  C) 59  D) 85  E) 99  ``` ``` Impedance A) 13  B) 23  C) 59  D) 85  E) 97  ``` ``` A) 0.28 A B) 0.40 A C) 0.75 A D) 1.1 A E) 1.6 A ``` ``` A) 0.47 B) 0.54 C) 0.64 D) 0.88 E) 28.3 ``` A) The voltage leads the current. B) The circuit is more capacitive than inductive. C) The voltage and current are exactly out of phase. D) The voltage and current are in phase. E) The phase angle for this circuit is positive.

Answer 35

``` B) 110 V A) 59 Ohms (lowest option!) A) 13 Ohms (lowest option!) E) 97 Ohms (Impedance) D) 1.1 A D) 0.88 B) The circuit is more capacitive than inductive. ```

Question 36

``` *5 PART QUESTION, TABLE to determine answers: A) 0.25 A B) 0.43 A C) 0.50 A D) 0.86 A E) 1.08 A ``` ``` A) 11  B) 22  C) 349  D) 486  E) 1240  ``` ``` A) 150 V B) 212 V C) 300 V D) 414 V E) 533 V ``` ``` A) 0.40 B) 0.57 C) 0.81 D) 1.4 E) 5.5 ``` ``` A) 37.0 W B) 64.5 W C) 73.3 W D) 95.4 W E) 129 W ```

Answer 36

``` B) 0.43 A C) 349 Ohms B) 212 V B) 0.57 A) 37.0 W ```

Question 37

``` ***10 PART QUESTION (broken up in 2) Pt.1 300 Ohm Resistor A) 180 V B) 255 V C) 300 V D) 360 V E) 480 V ``` ``` A) 150  B) 190  C) 360  D) 390  E) 440  ``` ``` A) 150  B) 190  C) 360  D) 390  E) 440  ``` ``` A) 150  B) 190  C) 360  D) 390  E) 440  ``` ``` A) 0.46 A B) 0.52 A C) 0.65 A D) 0.78 A E) 0.85 A ```

Answer 37

``` B) 255 V E) 440 Ohms CR B) 190 Ohms IR D) 390 Ohms I C) 0.65 A ```

Question 38

``` ***10 PART QUESTION (broken up in 2) Pt.2 300 Ohm Resistor A) 26∞ B) ñ32∞ C) 38∞ D) ñ40∞ E) 50∞ ``` ``` A) 48 W B) 54 W C) 63 W D) 83 W E) 112 W ``` ``` A) 120 V B) 180 V C) 190 V D) 260 V E) 290 V ``` ``` A) 120 V B) 140 V C) 190 V D) 260 V E) 290 V ``` ``` A) 120 V B) 180 V C) 190 V D) 210 V E) 290 V ```

Answer 38

``` D) ñ40∞ C) 63 W A) 120 V I C) 190 V R E) 290 V C ```

Question 39

``` A) 22 W B) 81 W C) 166 W D) 193 W E) 102 W ```

Answer 39

D) 193 W

Question 40

``` A) 52 mH B) 74 mH C) 0.12 H D) 2.1 H E) 13 H ```

Answer 40

A) 52 mH

Question 41

GRAPH: shows impedance as a function of frequency | At what point will circuit resonate?

Answer 41

B) f2

Question 42

``` A) 11.9 Hz B) 69.4 Hz C) 1.06 ◊ 102 Hz D) 8.27 ◊ 102 Hz E) 1.30 ◊ 103 Hz ```

Answer 42

E) 1.30 ◊ 103 Hz

Question 43

``` CA/CB. A) 0.44 B) 0.27 C) 3.7 D) 1.8 E) 2.4 ```

Answer 43

B) 0.27

Question 44

``` A) 2.4 ◊ 10ñ11 F B) 3.6 ◊ 10ñ11 F C) 4.4 ◊ 10ñ11 F D) 6.8 ◊ 10ñ11 F E) 8.8 ◊ 10ñ11 F ```

Answer 44

E) 8.8 ◊ 10ñ11 F

Question 45

``` A) 0.02 A B) 0.03 A C) 0.05 A D) 0.09 A E) 0.12 A ```

Answer 45

C) 0.05 A

Question 46

A) When the current in the inductor is zero, I/t = 0 A/s. B) The circuit will allow dc as well as ac current to flow. C) The magnetic field in the inductor is a maximum at t = 0 s. D) The charge on the capacitor will be a maximum at t = 4.2 ◊ 10ñ7 s. E) As the current through the inductor decreases, the induced emf in the coil is directed opposite to the direction of the current.

Answer 46

C) The magnetic field in the inductor is a maximum at t = 0 s.

Question 47

A) Doping makes the charge carriers mobile. B) Doping makes the charge carriers immobile. C) Doping makes the semiconducting material non-conducting. D) Doping increases the conductive properties of the semiconductors. E) Doping converts the semiconducting material into a metallic material like copper.

Answer 47

D) Doping increases the conductive properties of the semiconductors.

Question 48

A) the bias voltages are reversed. B) they are made from different materials. C) one is a bipolar transistor and the other is not. D) one conducts electricity and the other does not. E) the current directions are the same while the voltages are reversed.

Answer 48

A) the bias voltages are reversed.

Question 49

``` A) silicon doped with boron B) silicon doped with gallium C) germanium doped with boron D) silicon doped with phosphorus E) germanium doped with gallium ```

Answer 49

D) silicon doped with phosphorus

Question 50

A) A diode is fabricated by forming junctions between one n-type and two p-type semiconductors or one p-type and two n-type semiconductors. B) At an n-p junction in a diode that is not connected to a battery, an electric field exists across the junction. C) A battery can be connected to a diode so that a continual flow of charge results. D) A diode connected to an ac source allows current to flow only in one direction. E) Holes move in a diode under a forward-bias condition.

Answer 50

A) A diode is fabricated by forming junctions between one n-type and two p-type semiconductors or one p-type and two n-type semiconductors.

Question 51

``` A) 2.87 B) 2.32 C) 0.430 D) 0.348 E) 0.253 ```

Answer 51

D) 0.348

Question 52

``` A) V = 0.6 sin[(1.1 ◊ 106 rad/s)t] B) V = 0.6 sin[(1.2 ◊ 103 rad/s)t] C) V = 1.2 sin[(5.3 ◊ 106 rad/s)t] D) V = 1.2 sin[(2.3 ◊ 105 rad/s)t] E) V = 2.8 sin[(4.6 ◊ 106 rad/s)t] ```

Answer 52

B) V = 0.6 sin[(1.2 ◊ 103 rad/s)t]

Question 53

``` A) R1 = R2 = R3 B) R1 = 2R2 C) R1 = R2 D) R1 = R3 E) R2 = R3 ```

Answer 53

D) R1 = R3

Question 54

``` 6 PART QUESTION: A) 84.9 V B) 138 V C) 151 V D) 169 V E) 240 V ``` ``` A) 60  B) 188  C) 377  D) 514  E) 754  ``` ``` A) 50  B) 190  C) 195  D) 240  E) 210  ``` ``` A) 2.40 A B) 1.71 A C) 1.33 A D) 0.617 A E) 0.437 A ``` ``` A) 2.40 A B) 1.71 A C) 1.33 A D) 0.617 A E) 0.437 A ``` ``` A) 9.50 W B) 21.2 W C) 74.9 W D) 113 W E) 138 W ```

Answer 54

``` A) 84.9 V B) 188 Ohms C) 195 Ohms E) 0.437 A D) 0.617 A (Peak Current) A) 9.50 W ```