1. True/False Capacitive reactance decreases with more capacitance and higher frequencies for sine-wave ac voltage applied.

2.True/False The opposition that resistance offers remains the same for dc and ac circuits.

3.True/False For any capacitor, the 180 phase relationship between v_c and i_c exists for all values of capacitance or any frequency of sine wave alternating voltage.

4.True/False) When series voltage drops that are out of phase are combined, they can be added without taking the phase difference into account.

5.True/False Inductance is the ability of a conductor to produce induced voltage when the current varies.

6.True/False Induced voltage is the result of flux cutting across an insulator.

7.True/False One henry is the amount of inductance that allows one volt to be induced when the current changes at the rate of one ampere per second.

8.True/False A steady dc current can induce a voltage in a coil.

9.True/False The amount of inductive reactance equals two pi times the frequency plus the inductance.

10.True/False Very often X_L can be determined from voltage and current measurements.

11.True/False Although L can be determined when X_L and f are known, its value is determined strictly by its physical construction.

12.True/False The amount of current in an ac circuit with only inductive reactance is equal to the applied voltage divided by the inductance.

13.True/False In a series RL circuit, I and IR have a phase angle of 0.

14.True/False In a series circuit, the higher the value of X_L compared with R, the more inductive the circuit.

15.True/False When a coil has series resistance, alternating current is limited by only R.

Multiple Choice

16.What circuit has different branch currents but one common voltage?

A.Amplifier

B.Bridge

C.Series

D.Parallel

17.What is the component called that is used to pass ac signal to the load resistor while blocking low frequencies and dc?

A.Bypass capacitor

B.Coupling capacitor

C.Inductor

D.Varactor

18.When a capacitor and resistor are connected in series, the current is limited by

A.X_C only

B.R only

C.both X_C and R

D.neither R nor X_C

19.In a series RC circuit, V_R and I are

A.in phase

B.out of phase by 45

C.out of phase by 90

D.out of phase by -90

20.When calculating capacitive current, capacitive reactance applies

A.only to sine waves

B.only to square waves

C.only to pulse waves

D.to any nonsinusoidal waveform

21.The unit of mutual inductance is the

A.gilbert

B.Maxwell

C.henry

D.Oersted

22.Mutual inductance is also called

A.mutual coupling

B.flux coupling

C.link coupling

D.inductive linking

23. What component uses mutual inductance to step up or step down an alternating voltage?

A.Inductor

B.Capacitor

C.Kesistor

D.Transformer

24.The ratio of the number of turns in the primary to the number in the secondary is the

A.transformer ratio

B.coupling coefficient

C.coupling ratio

D.turns ratio

25.With zero losses assumed for the transformer, the power in the secondary

A.is always more than the primary

B.is always less than the primary

C.is equal to the power in the primary

D.is equal to I_S times R_S

26.An advantage of using a transformer with a separate winding secondary is

A.electrical isolation

B.dc can be coupled to the secondary

C.it is compact

D.it is inexpensive

27.The dc resistance between the primary and secondary windings of a transformer should always measure

A.0

B.

C.75

D.1500

28.Frequency is equal to

A.2p x T

B.2p/T

C.p/T

D.1/T

29.Inductive reactance is measured in

A.watts

B.volt-amperes

C.ohms

D.Siemens

30.X_L equals

A.1/2pfL

B.2pfL

C.2p/fL

D.f/2pL

31.How much is the X_L for a coil with negligible resistance that has 62.8 V across it with 0.1 A of current?

A.62.8

B.628

C.6280

D.62,800

32.A parallel circuit has

A.different branch currents

B.different voltage drops

C.one common current

D.a total voltage equal to individual voltage drops

33.Inductance has the useful characteristic of providing more ohms of reactance at

A.lower frequencies

B.higher frequencies

C.resonant frequencies

D.harmonic frequencies

34.In an RL circuit, as the frequency increases

A.R increases

B.R decreases

C.X_L increases

D.X_L decreases

35.A trigonometric function of any angle of a right triangle, equal to the ratio of the opposite side to the adjacent side of a triangle is the

A.sine

B.cosine

C.tangent

D.cotangent

36.If the internal resistance of a coil is low

A.its Q is low

B.its Q is high

C.its Q is zero

D.its Q is infinite

37.How much is Z_T for a 100 R in series with a 100 inductor?

A.100

B.1000

C.1410

D.141

38.What is the phase angle for the voltage across X_L with respect to the current through L?

A.V_L lags I_L by 90

B.V_L leads I_L by 90

C.V_L leads I_L by 45

D.V_L is in phase with I_L

Essay

1.Explain the reason for RF shielding in a circuit.

2.Define what is meant by the Q of a coil (draw schematic).