Question 1

The amount of current in an ac circuit with only inductive reactance is ______________ the applied voltage divided by X_L.

Accepted Answer

equal to

Question 2

The general use of ______________ is to provide minimum reactance for relatively low frequencies but more for higher frequencies.

Accepted Answer

inductance

Question 3

Inductor values ______________ 1 mH are generally not practical for use in electronic circuits.

Accepted Answer

below

Question 4

With iron-core coils, the hysteresis and eddy-current losses ______________ with frequency.

Accepted Answer

The answer of With iron-core coils, the hysteresis and eddy-current...

Question 5

For an inductor, the induced voltage, V_L always ______________ the current by 90°.

Accepted Answer

The answer of For an inductor, the induced voltage, V_L...

Question 6

When ______________ current flows in an inductance, the amount of current is much less than the dc resistance alone would allow.

Accepted Answer

The answer of When ______________ current flows in an inductance,...

Question 7

Inductive reactance is measured in ______________.

Accepted Answer

The answer of Inductive reactance is measured in ______________....

Question 8

There is no inductive reactance for steady ______________ current.

Accepted Answer

The answer of There is no inductive reactance for steady...

Question 9

The polarity of an inductor's counter emf is always such that it ______________ a change in current.

Accepted Answer

The answer of The polarity of an inductor's counter emf...

Question 10

______________ reactance is equal to two times pi times frequency times inductance.

Accepted Answer

The answer of ______________ reactance is equal to two times...

Question 11

Inductor values ______________ 1 μH are generally not practical for use in electronic circuits.

Accepted Answer

The answer of Inductor values ______________ 1 μH are generally...

Question 12

For the most part, inductor values below what value are not practical for use in electronic circuits?
A) 1?H
B) 100?H
C) 100 mH
D) 1 mH

Accepted Answer

Inductors with values below 1 microhenry (1?H) are generally not practical for use in electronic circuits due to their very low inductance, making them ineffective at storing energy or filtering signals at the frequencies typically used in electronics.

Question 13

With iron-core coils, the hysteresis and eddy-current losses
A) increase with frequency
B) decrease with frequency
C) are negligible
D) are extremely high regardless of the frequency

Accepted Answer

Hysteresis and eddy-current losses in iron-core coils increase with frequency because both phenomena are related to the rate of change of the magnetic field within the material. Higher frequencies mean more rapid changes in the magnetic field, leading to greater losses.

Question 14

For an inductor, the induced voltage V_L always A) lags the current I by 90° B) leads the current I by 90° C) lags the current I by 180° D) leads the current I by 180°

Accepted Answer

In an inductor, the induced voltage leads the current by 90 degrees due to the property of inductance where the magnetic field generated by the current opposes changes in current, causing the voltage to lead.

Question 15

Frequency is equal to
A) 2p x T
B) 2p/T
C) p/T
D) 1/T

Accepted Answer

Frequency is defined as the number of cycles per unit time, which is mathematically represented as the inverse of the period (T), hence 1/T.

Question 16

When alternating current flows in an inductance,
A) the current is less than the dc resistance alone would allow
B) the current is more than the dc resistance alone would allow
C) the ac current is not affected by dc resistance
D) the ac current is not affected by inductance

Accepted Answer

Inductance in an AC circuit causes a phase shift between voltage and current, effectively increasing the circuit's impedance beyond just the DC resistance. This results in less current flow than if only the DC resistance were present.

Question 17

X_L equals A) 1/2?fL B) 2?fL C) 2?/fL D) f/2?L

Accepted Answer

The inductive reactance (X_L) is given by the formula X_L = 2πfL, where f is the frequency and L is the inductance.

Question 18

What is the inductive reactance for steady direct current?
A) 600 ?
B) 75 ?
C) ? ?
D) 0 ?

Accepted Answer

Inductive reactance is a property that only affects alternating current (AC) circuits, as it depends on the frequency of the alternating current. For direct current (DC), which has a frequency of 0 Hz, the inductive reactance is 0 ohms because DC does not change direction or frequency, thus not inducing any reactance in the circuit.

Question 19

Which of the following is not an example of how X_L is generally used? A) Block dc B) High opposition to high frequency ac C) Little opposition to dc D) Low opposition to low frequency ac

Accepted Answer

X_L, or more generally, inductors, do not block DC; they allow DC to pass with little opposition. Inductors provide high opposition to high-frequency AC and low opposition to low-frequency AC, but they do not inherently block DC.

Question 20

What results from an inductor's counter emf with a varying current?
A) Transformer action
B) Impedance
C) Resistance
D) Inductive reactance

Accepted Answer

Inductive reactance results from an inductor's counter emf when there is a varying current, as it opposes changes in current through the inductor.

Quiz 21: Inductive Reactance

The amount of current in an ac circuit with only inductive reactance is ______________ the applied voltage divided by XL.

The general use of ______________ is to provide minimum reactance for relatively low frequencies but more for higher frequencies.

Inductor values ______________ 1 mH are generally not practical for use in electronic circuits.

With iron-core coils, the hysteresis and eddy-current losses ______________ with frequency.

For an inductor, the induced voltage, VL always ______________ the current by 90°.

When ______________ current flows in an inductance, the amount of current is much less than the dc resistance alone would allow.

Inductive reactance is measured in ______________.

There is no inductive reactance for steady ______________ current.

The polarity of an inductor's counter emf is always such that it ______________ a change in current.

______________ reactance is equal to two times pi times frequency times inductance.

Inductor values ______________ 1 μH are generally not practical for use in electronic circuits.

For the most part, inductor values below what value are not practical for use in electronic circuits?

With iron-core coils, the hysteresis and eddy-current losses

For an inductor, the induced voltage VL always

Frequency is equal to

When alternating current flows in an inductance,

XL equals

What is the inductive reactance for steady direct current?

Which of the following is not an example of how XL is generally used?

What results from an inductor's counter emf with a varying current?

The amount of current in an ac circuit with only inductive reactance is ______________ the applied voltage divided by X_L.

For an inductor, the induced voltage, V_L always ______________ the current by 90°.

For an inductor, the induced voltage V_L always

X_L equals

Which of the following is not an example of how X_L is generally used?