Question 1

At the cutoff frequency of a filter circuit, the output voltage is:

Accepted Answer

A) -20 dB. 
B) -40 dB. 
C) -3 dB. 
D) -10 dB. 
A) -20 dB. 
B) -40 dB. 
C) -3 dB. 
D) -10 dB.

Question 2

-The frequency response curve in Figure 19-5 represents the output from the ________, and the bandwidth is ________.

Accepted Answer

A) band-pass filter, 1050 Hz 
B) band-pass filter, 678 Hz 
C) band-reject filter, 1050 kHz 
D) two-pole high-pass filter, 1050 Hz 
A) band-pass filter, 1050 Hz 
B) band-pass filter, 678 Hz 
C) band-reject filter, 1050 kHz 
D) two-pole high-pass filter, 1050 Hz

Question 3

The input frequency of a single-pole, low-pass active filter increases from 1.5 kHz to 150 kHz. If the critical frequency is 1.5 kHz, the gain decreases by ________.

Accepted Answer

A) 60 dB 
B) 3 dB 
C) 40 dB 
D) 20 dB 
A) 60 dB 
B) 3 dB 
C) 40 dB 
D) 20 dB

Question 4

-A three-terminal voltage regulator ________.

Accepted Answer

A) comes in a variety of voltage and current ratings 
B) is available in both positive and negative voltage ratings 
C) is very durable 
D) all of the above 
A) comes in a variety of voltage and current ratings 
B) is available in both positive and negative voltage ratings 
C) is very durable 
D) all of the above

Question 5

An op-amp integrator will produce a linear increasing output voltage for a constant negative
input voltage until cutoff is reached.

Accepted Answer

A) True 
 B)False

Question 6

-If 22 V in the pass-band is input to the circuit in Figure 19-4, what is the output voltage at fCO?

Accepted Answer

A) 8.92 V 
B) 7.75 V 
C) 31.1 V 
D) 15.6 V 
A) 8.92 V 
B) 7.75 V 
C) 31.1 V 
D) 15.6 V

Question 7

If all four input resistors to a summing amplifier are   and the feedback resistor is   , then the gain equals ________.

Accepted Answer

A) 4 
B) 2.2 
C) 1 
D) unknown 
A) 4 
B) 2.2 
C) 1 
D) unknown

Question 8

-If the output voltage is 27.4 V at 822 Hz in Figure 19-5, what is the output voltage at 1.5 kHz?

Accepted Answer

A) 27.4 V 
B) 13.7 V 
C) 6.85 V 
D) 19.4 V 
A) 27.4 V 
B) 13.7 V 
C) 6.85 V 
D) 19.4 V

Question 9

The purpose of a comparator is to ________.

Accepted Answer

A) detect the occurrence of a changing input voltage 
B) produce a change in output when an input voltage equals a reference voltage 
C) maintain a constant output when the dc input voltage changes 
D) amplify an input voltage 
A) detect the occurrence of a changing input voltage 
B) produce a change in output when an input voltage equals a reference voltage 
C) maintain a constant output when the dc input voltage changes 
D) amplify an input voltage

Question 10

The basic op-amp square wave oscillator is actually a:

Accepted Answer

A) Wein-bridge oscillator. 
B) resistor-capacitor (R 
C) time constant oscillator. 
C) sine wave oscillator. 
D) all of these. 
A) Wein-bridge oscillator. 
B) resistor-capacitor (R 
C) time constant oscillator. 
C) sine wave oscillator. 
D) all of these.

Question 11

In a series voltage regulator, the four circuit blocks are:

Accepted Answer

A) error detector, reference voltage, series regulator, sampling circuit. 
B) control element, reference voltage, error detector, sampling circuit. 
C) reference voltage, series load, reference voltage, current limiter. 
D) control element, reference voltage, error detector, current limiter. 
A) error detector, reference voltage, series regulator, sampling circuit. 
B) control element, reference voltage, error detector, sampling circuit. 
C) reference voltage, series load, reference voltage, current limiter. 
D) control element, reference voltage, error detector, current limiter.

Question 12

-If the inputs are 4. , the output voltage equals ________.

Accepted Answer

A) -6.5 V 
B) 13 V 
C) -13 V 
D) 6.5 V 
A) -6.5 V 
B) 13 V 
C) -13 V 
D) 6.5 V

Question 13

-If   in Figure 19-3, the output voltage at fCO equals ________.

Accepted Answer

A) 13 VP 
B) 0 VP 
C) 49.5 VP 
D) 44.2 VP 
A) 13 VP 
B) 0 VP 
C) 49.5 VP 
D) 44.2 VP

Question 14

If an inverting amplifier has a capacitor in the feedback loop, the circuit is known as the ________. When a square wave input is applied, the output is a ________ wave.

Accepted Answer

A) integrator, square 
B) open loop, triangle 
C) differentiator, triangle 
D) integrator, triangle 
A) integrator, square 
B) open loop, triangle 
C) differentiator, triangle 
D) integrator, triangle

Question 15

-If the output voltage is 6 V at 1500 Hz in Figure 19-5, what is the output voltage at 822 Hz?

Accepted Answer

A) 4.24 V 
B) 1.06 V 
C) 8.49 V 
D) 2.12 V 
A) 4.24 V 
B) 1.06 V 
C) 8.49 V 
D) 2.12 V

Question 16

In an inverting input op-amp integrator supplied with a square wave pulse or a step, the output is a:

Accepted Answer

A) opposite phase ramp. 
B) same phase ramp. 
C) opposite phase square wave. 
D) sine wave. 
A) opposite phase ramp. 
B) same phase ramp. 
C) opposite phase square wave. 
D) sine wave.

Question 17

Op-amp comparators are often used as zero-level detectors.

Accepted Answer

A) True 
 B)False

Question 18

-If   equals ________.

Accepted Answer

A) 3.3 V 
B) -3.3 V 
C) -13 V 
D) 13 V 
A) 3.3 V 
B) -3.3 V 
C) -13 V 
D) 13 V

Question 19

-The prime characteristic of the filter in Figure 19-4 is ________.

Accepted Answer

A) it only works in a high-pass configuration 
B) the filter roll-off below the corner frequency is 40 dB/decade 
C) it has the largest response of any filter type 
D) nothing special 
A) it only works in a high-pass configuration 
B) the filter roll-off below the corner frequency is 40 dB/decade 
C) it has the largest response of any filter type 
D) nothing special

Question 20

-A series-pass voltage regulator has ________.

Accepted Answer

A) a load 
B) a shunt regulator 
C) an error amplifier 
D) all of these 
A) a load 
B) a shunt regulator 
C) an error amplifier 
D) all of these

Exam 19: Circuit Theorems in Ac Analysis

At the cutoff frequency of a filter circuit, the output voltage is:

-The frequency response curve in Figure 19-5 represents the output from the ________, and the bandwidth is ________.

The input frequency of a single-pole, low-pass active filter increases from 1.5 kHz to 150 kHz. If the critical frequency is 1.5 kHz, the gain decreases by ________.

-A three-terminal voltage regulator ________.

An op-amp integrator will produce a linear increasing output voltage for a constant negative input voltage until cutoff is reached.

-If 22 V in the pass-band is input to the circuit in Figure 19-4, what is the output voltage at fCO?

If all four input resistors to a summing amplifier are and the feedback resistor is , then the gain equals ________.

-If the output voltage is 27.4 V at 822 Hz in Figure 19-5, what is the output voltage at 1.5 kHz?

The purpose of a comparator is to ________.

The basic op-amp square wave oscillator is actually a:

In a series voltage regulator, the four circuit blocks are:

-If the inputs are 4. , the output voltage equals ________.

-If in Figure 19-3, the output voltage at fCO equals ________.

If an inverting amplifier has a capacitor in the feedback loop, the circuit is known as the ________. When a square wave input is applied, the output is a ________ wave.

-If the output voltage is 6 V at 1500 Hz in Figure 19-5, what is the output voltage at 822 Hz?

In an inverting input op-amp integrator supplied with a square wave pulse or a step, the output is a:

Op-amp comparators are often used as zero-level detectors.

-If equals ________.

-The prime characteristic of the filter in Figure 19-4 is ________.

-A series-pass voltage regulator has ________.

Quantities and Units

Voltage, Current, and Resistance

Ohms Law

Energy and Power

Series Circuits

Parallel Circuits

Series-Parallel Circuits

Circuit Theorems and Conversions

Branch, Loop, and Node Analyses

Magnetism and Electromagnetism

Introduction to Alternating Current and Voltage

Capacitors

Inductors

Transformers

RC Circuits

RL Circuits

RlC Circuits and Resonance

Passive Filters

Time Response of Reactive Circuits

Three-Phase Systems in Power Applications

Filters

-The frequency response curve in Figure 19-5 represents the output from the , and the bandwidth is .

If an inverting amplifier has a capacitor in the feedback loop, the circuit is known as the . When a square wave input is applied, the output is a wave.