Deck 17: Inductance in Alternating Current Circuits

Question 1

The current-limiting property of an inductor is called _____.

A) resistance
B) inductance
C) reactance
D) henrys

Answer 1

C

Question 2

The unit of inductance is the _____.

A) reactance
B) henry
C) ohm
D) hertz

Answer 2

B

Question 3

An inductor is connected to a 60 Hz circuit. The inductive reactance is 75.4 Ω . What is the inductance of the inductor?

A) 0.2 H
B) 5 H
C) 284 H
D) 4524 H

Answer 3

A

Question 4

Two inductors are connected in parallel to a 120-V, 60-Hz supply. The values of the inductors are 0.15 H and 0.225 H. The total inductive reactance is _____.

A) 3.54 A
B) 4.84 A
C) 5.41 A
D) 6.12 A

Question 5

Two inductors are connected in series to a 120-V, 60-Hz supply. The values of the inductors are 1.5 H and 2.5 H. The total inductive reactance is _____.

A) 42.5 Ω
B) 365.5 Ω
C) 553.44 Ω
D) 1508 Ω

Question 6

An inductor is connected to a 120-V, 60-Hz supply. The current in the circuit is 2.4 A. What is the inductive reactance?

A) 57.08 Ω
B) 104.8 Ω
C) 288 Ω
D) 50  Ω

Question 7

The symbol for reactive power of an inductor is _____.

A) W
B) VA
C) VARs
D) P

Question 8

An inductor with an inductance of three henrys (H) is to be connected to a 60 Hz circuit. What will the inductive reactance be?

A) 180 Ω
B) 360 Ω
C) 565 Ω
D) 1131 Ω

Question 9

In a pure inductive circuit, current _____.

A) lags voltage by 90 °
B) leads voltage by 90 °
C) is in phase with voltage
D) lags voltage by 180 °

Question 10

Circuits are generally considered to contain _____ when any type of load that contains a coil is used.

A) inductance
B) reactance
C) resistance
D) volt-amperes

Question 11

An inductor is connected to a 240-V, 60-Hz supply. The current in the circuit is 5 A. What is the inductance of the inductor?

A) )0048 H
B) )0075 H
C) )1185 H
D) )127 H

Question 12

Two inductors are connected in parallel to a 120-V, 60-Hz supply. The values of the inductors are 1.5 H and 2.5 H. The total inductive reactance is _____.

A) 525.5 Ω
B) 533.49 Ω
C) 942.5 Ω
D) 1508 Ω

Question 13

An inductor has an inductive reactance of 64 Ω , and a wire resistance of 36 Ω . What is the impedance of the inductor?

A) 10 Ω
B) 28 Ω
C) 73.4 Ω
D) 82.92 Ω

Question 14

When a magnetic field continually changes magnitude and direction, a voltage is continually being induced in the coil. This voltage is called _____ voltage.

A) conducted
B) induced
C) applied
D) inductive

Question 15

The total current-limiting effect is called _____.

A) reluctance
B) impedance
C) resistive reactance
D) inductive resistance

Question 16

The amount of resistance compared with the inductive reactance determines the _____ of the coil.

A) power factor (PF)
B) quality (Q)
C) phase angle ( θ )
D) reactance (X)

Question 17

The symbol for reactance is _____.

A) R _L
B) X _L
C) L
D) H

Question 18

The symbol X_L stands for _____.

A) resistance
B) inductive resistance
C) inductive reactance
D) resistive reactance

Question 19

Two inductors are connected in series to a 120-V, 60-Hz supply. The values of the inductors are 0.175 H and 0.255 H. The total circuit current is _____.

A) 0.74 A
B) 1.02 A
C) 1.85 A
D) 3.067 A

Question 20

Volt-amperes-reactive is used to measure the _____ in a pure inductive circuit.

A) watts
B) reactive power
C) volt amperes
D) joules

Question 21

An inductor has an inductive reactance of 12 Ω , and a wire resistance of 16 Ω . What is the impedance of the inductor?

A) 4 Ω
B) 20 Ω
C) 28 Ω
D) 400 Ω