# Gibilisco - Inductive Reactance

18 Questions | Total Attempts: 371  Settings  • 1.
As the number of turns in a coil that carries ac increases without limit, the current in the coilwill
• A.

Eventually become very large.

• B.

Stay the same.

• C.

Decrease, approaching zero.

• D.

Be stored in the core material.

• 2.
As the number of turns in a coil increases, the reactance at a constant frequency
• A.

Increases.

• B.

Decreases.

• C.

Stays the same.

• D.

Is stored in the core material.

• 3.
As the frequency of an ac wave gets lower, the value of XL for a particular coil of wire
• A.

Increases.

• B.

Decreases.

• C.

Stays the same.

• D.

Depends on the voltage.

• 4.
Suppose a coil has an inductance of 100 mH. What is the reactance at a frequency of 1000Hz?
• A.

0.628 Ω

• B.

6.28 Ω

• C.

62.8 Ω

• D.

628 Ω

• 5.
Suppose a coil shows an inductive reactance of 200 Ω at 500 Hz. What is its inductance?
• A.

0.637 H

• B.

628 H

• C.

63.7 mH

• D.

628 mH

• 6.
Imagine a 400-µH inductor with a reactance of 33 Ω. What is the frequency?
• A.

13 kHz

• B.

0.013 kHz

• C.

83 kHz

• D.

83 MHz

• 7.
Suppose an inductor has XL = 555 Ω at f = 132 kHz. What is L?
• A.

670 mH

• B.

670 µH

• C.

460 mH

• D.

460 µH

• 8.
Suppose a coil has L = 689 µH at f = 990 kHz. What is XL?
• A.

682 Ω

• B.

4.28 Ω

• C.

4.28 kΩ

• D.

4.28 MΩ

• 9.
Suppose an inductor has L = 88 mH with XL = 100 Ω. What is f?
• A.

55.3 kHz

• B.

55.3 Hz

• C.

181 kHz

• D.

181 Hz

• 10.
Each point in the RL plane
• A.

Corresponds to a unique resistance.

• B.

Corresponds to a unique inductance.

• C.

Corresponds to a unique combination of resistance and inductive reactance.

• D.

Corresponds to a unique combination of resistance and inductance.

• 11.
If the resistance R and the inductive reactance XL both are allowed to vary from zero tounlimited values, but are always in the ratio 3:1, the points in the RL plane for all the resultingimpedances will lie along
• A.

A vector pointing straight up.

• B.

A vector pointing east.

• C.

A circle.

• D.

A ray of indefinite length, pointing outward from the origin.

• 12.
Each specific complex impedance value defined in the form R + jXL
• A.

Corresponds to a specific point in the RL plane.

• B.

Corresponds to a specific inductive reactance.

• C.

Corresponds to a specific resistance.

• D.

All of the above are true.

• 13.
A vector is defined as a mathematical quantity that has
• A.

Magnitude and direction.

• B.

Resistance and inductance.

• C.

Resistance and reactance.

• D.

Inductance and reactance.

• 14.
In an RL circuit, as the ratio of inductive reactance to resistance (XL/R) decreases, the phaseangle
• A.

Increases.

• B.

Decreases.

• C.

Stays the same.

• D.

Becomes alternately positive and negative.

• 15.
In a circuit containing inductive reactance but no resistance, the phase angle is
• A.

Constantly increasing.

• B.

Constantly decreasing.

• C.

Equal to 0°.

• D.

Equal to 90°.

• 16.
If the inductive reactance and the resistance in an RL circuit are equal (as expressed in ohms),then what is the phase angle?
• A.

• B.

45°

• C.

90°

• D.

It depends on the actual values of the resistance and the inductive reactance.

• 17.
Consider an RL circuit that consists of a 100-µH inductor and a 100-Ω resistor. What is thephase angle at a frequency of 200 kHz?
• A.

45.0°

• B.

51.5°

• C.

38.5°

• D.

There isn’t enough data given to calculate it.

• 18.
Suppose an RL circuit has an inductance of 88 mH, and the resistance is 95 Ω. At 800 Hz,what is the phase angle?
• A.

78°

• B.

12°

• C.

43°

• D.

47° Back to top