HAM Radio Extra Class Test Advanced Electrical Principles Questions and Answers

Question 1

In a series RLC circuit at resonance, what is the relationship between capacitive reactance (Xc) and inductive reactance (Xl)?

Accepted Answer

Xc and Xl are equal in magnitude.

Answer

Xc is infinite, and Xl is zero.

Answer

Xc is much larger than Xl.

Answer

Xl is much larger than Xc.

Question 2

A technician is designing a filter for a radio receiver. The goal is to create a circuit that has a very narrow bandwidth to select a specific frequency while rejecting adjacent ones. Which of the following characteristics should the resonant circuit have?

Accepted Answer

A high Q factor

Answer

A low Q factor

Answer

A high resistance value

Answer

A purely capacitive impedance

Question 3

What is the primary characteristic of a parallel resonant circuit (tank circuit) at its resonant frequency?

Accepted Answer

The circuit impedance is at its maximum.

Answer

The line current is at its maximum.

Answer

The circuit impedance is at its minimum.

Answer

The circuit acts as a short circuit.

Question 4

How does the inductive reactance of a component change as the frequency of the applied AC signal increases?

Accepted Answer

It increases proportionally.

Answer

It decreases proportionally.

Answer

It remains constant.

Answer

It first increases, then decreases.

Question 5

Which of the following best describes impedance in an AC circuit?

Accepted Answer

The total opposition to current flow, including both resistance and reactance.

Answer

The opposition to current flow from inductors only.

Answer

The opposition to current flow from capacitors only.

Answer

The in-phase component of opposition to AC current.

Question 6

In a purely capacitive AC circuit, what is the phase relationship between the current and the voltage?

Accepted Answer

Current leads voltage by 90 degrees.

Answer

Current and voltage are in phase.

Answer

Current lags voltage by 90 degrees.

Answer

Voltage lags current by 180 degrees.