1475 + Mcqs in Electronic Devices Page 20 McqOptions

951.	The output signal of an op-amp is ________ out of phase with its input signal connected to the inverting input terminal.
A.	0
B.	90
C.	180
D.	270
Answer» D. 270

Discussion

952.	The output offset voltage is determined by ________.
A.	the input offset voltage and input offset current
B.	the closed-loop gain
C.	both the input offset voltage and the closed-loop gain
D.	None of the above
Answer» B. the closed-loop gain

Discussion

953.	In a differential connection, the signals that are opposite at the inputs are ________ amplified, and those that are common to the two inputs are ________ amplified.
A.	slightly, slightly
B.	slightly, highly
C.	highly, highly
D.	highly, slightly
Answer» E.

Discussion

954.	What is the response time of light-emitting diodes (LEDs)?
A.	Less than 100 ns
B.	50 ms
C.	100 ms to 300 ms
D.	400 ms
Answer» B. 50 ms

Discussion

955.	What is the response time of LCDs?
A.	Less than 100 ns
B.	50 ms
C.	100 ms to 300 ms
D.	400 ms
Answer» D. 400 ms

Discussion

956.	The current capability of power diodes can be increased by placing two or more in series.
A.	True
B.	False
Answer» C.

Discussion

957.	Selectivity in a receiver is provided by the resonant circuits of the IF section.
A.	True
B.	False
Answer» B. False

Discussion

958.	An AM signal is made up of a carrier, an upper-side frequency, and a lower-side frequency.
A.	True
B.	False
Answer» B. False

Discussion

959.	Frequency modulation is achieved by varying the frequency of an oscillator with a modulating signal.
A.	True
B.	False
Answer» B. False

Discussion

960.	A good op-amp has low voltage gain, low output impedance, and high input impedance.
A.	True
B.	False
Answer» C.

Discussion

961.	A non-inverting amplifier has a higher input impedance and a lower output impedance than the op-amp itself (without feedback).
A.	True
B.	False
Answer» B. False

Discussion

962.	What type of temperature coefficient do thermistors have?
A.	Positive
B.	Negative
C.	Either positive or negative
D.	None of the above
Answer» D. None of the above

Discussion

963.	Which of the following diodes has a negative-resistance region?
A.	Schottky
B.	Varactor
C.	Tunnel
D.	Power
Answer» D. Power

Discussion

964.	The tuning diode is a ________-dependent, variable ________.
A.	voltage, resistor
B.	current, capacitor
C.	voltage, capacitor
D.	current, inductor
Answer» D. current, inductor

Discussion

965.	Inverting amplifier connection is more widely used because it has ________.
A.	higher gain
B.	better frequency stability
C.	unit gain
D.	None of the above
Answer» E.

Discussion

966.	An operational amplifier is a ________ gain and ________ bandwidth differential amplifier.
A.	very low, narrow
B.	low, wide
C.	medium, narrow
D.	very high, wide
Answer» E.

Discussion

967.	The main feature of the differential amplifier is the ________ gain when opposite signals are applied to the inputs as compared to the ________ gain resulting from common inputs.
A.	very large, large
B.	very small, large
C.	very small, very large
D.	very large, very small
Answer» E.

Discussion

968.	The temperature coefficient can be ________ for different Zener levels.
A.	positive
B.	negative
C.	zero
D.	All of the above
Answer» E.

Discussion

969.	Introducing those impurity elements that have ________ valence electrons creates the n-type material.
A.	0
B.	3
C.	4
D.	5
Answer» E.

Discussion

970.	The reverse-bias current ________ with the increase of temperature.
A.	decreases
B.	increases
C.	remains the same
D.	None of the above
Answer» C. remains the same

Discussion

971.	Any electron that has left its parent atom has ________ energy state relative to any electron in the atomic structure.
A.	the same
B.	a lower
C.	a higher
D.	an undefined
Answer» D. an undefined

Discussion

972.	The diffused impurities with ________ valence electrons are called acceptor atoms.
A.	0
B.	3
C.	4
D.	5
Answer» C. 4

Discussion

973.	A(n) ________ is the simplest of semiconductor devices.
A.	diode
B.	transistor
C.	operational amplifier
D.	SCR
Answer» B. transistor

Discussion

974.	The reverse-saturation current level is typically measured in ________.
A.	pA
B.	<img src="/_files/images/electronic-devices-and-circuit-theory/mu.gif">
C.	A
D.	mA
E.	A
Answer» C. A

Discussion

975.	The depletion width ________ in the forward bias, which results in having a majority flow across the junction.
A.	widens
B.	remains unchanged
C.	shrinks
D.	widens and shrinks alternatively
Answer» D. widens and shrinks alternatively

Discussion

976.	The test current in a Zener diode IZT is the current defined by the ________ power level.
A.	0.25
B.	0.5
C.	0.75
D.	1.00
Answer» B. 0.5

Discussion

977.	The ac resistance of a diode is the ________ of the characteristic curve at the Q-point of operation.
A.	reciprocal of the slope
B.	slope
C.	midpoint
D.	average value
Answer» B. slope

Discussion

978.	The potential at which the characteristics curve vertical rise occurs is commonly referred to as the ________.
A.	offset
B.	threshold
C.	firing potential
D.	All of the above
Answer» E.

Discussion

979.	The ________ the current through a diode, the ________ the dc resistance level.
A.	higher, lower
B.	lower, lower
C.	lower, higher
D.	higher, higher
Answer» D. higher, higher

Discussion

980.	The heavier the current in a Zener diode in reverse bias, ________ dynamic resistance value.
A.	the more the
B.	the less the
C.	there is substantially more
D.	there is no change in the
Answer» C. there is substantially more

Discussion

981.	The demodulator recovers the audio signal from the IF output.
A.	True
B.	False
Answer» B. False

Discussion

982.	Varying the ________ can control the location of the Zener region.
A.	forward current
B.	doping levels
C.	forward voltage
D.	dc resistance
Answer» C. forward voltage

Discussion

983.	The term ________ is often used when comparing the resistance level of materials.
A.	permittivity
B.	inductivity
C.	conductivity
D.	resistivity
Answer» E.

Discussion

984.	The reverse recovery time of most commercial switching diodes is in the range of ________.
A.	picoseconds
B.	a few nanoseconds
C.	several microseconds
D.	milliseconds
Answer» C. several microseconds

Discussion

985.	Diodes are connected ________ to increase the current-carrying capacity.
A.	in series
B.	in parallel
C.	in parallel-series
D.	None of the above
Answer» C. in parallel-series

Discussion

986.	The purpose of the balanced modulator is to remove the carrier frequency.
A.	True
B.	False
Answer» B. False

Discussion

987.	The mixer takes the RF signal along with the audio signal to produce the IF signal.
A.	True
B.	False
Answer» C.

Discussion

988.	The IF of an FM receiver operates at a center frequency of 455 kHz.
A.	True
B.	False
Answer» C.

Discussion

989.	A balanced modulator is used in standard AM to obtain the sum and difference frequencies.
A.	True
B.	False
Answer» C.

Discussion

990.	What metal(s) is(are) used in the construction of Schottky diodes?
A.	Molybdenum
B.	Platinum
C.	Tungsten
D.	Silicon
E.	Any of the above
Answer» F.

Discussion

991.	What is the maximum temperature limit for liquid-crystal displays (LCDs)?
A.	10 C
B.	30 C
C.	60 C
D.	100 C
Answer» D. 100 C

Discussion

992.	Which of the following diodes is limited to the reverse-bias region in its region of operation?
A.	Schottky
B.	Tunnel
C.	Photodiode
D.	Rectifier
Answer» D. Rectifier

Discussion

993.	In filters, a single RC network is called a pole.
A.	True
B.	False
Answer» B. False

Discussion

994.	A band-pass filter passes all frequencies within a band between a lower and an upper cutoff frequency.
A.	True
B.	False
Answer» B. False

Discussion

995.	A second-order filter has a roll-off of 20 dB/decade.
A.	True
B.	False
Answer» C.

Discussion

996.	Butterworth filters have the characteristic of a very flat response in the passband and a roll-off of 20 dB/decade.
A.	True
B.	False
Answer» B. False

Discussion

997.	Which of the following areas is (are) applications of varactor diodes?
A.	FM modulators
B.	Automatic-frequency control devices
C.	Adjustable bandpass filters
D.	All of the above
Answer» E.

Discussion

998.	This is an approximate equivalent circuit for the ________ diode.
A.	Schottky
B.	varicap
C.	tunnel
Answer» B. varicap

Discussion

999.	Which of the following materials is (are) used in the manufacturing of thermistors?
A.	Ge
B.	Si
C.	A mixture of oxides of cobalt, nickel, strontium, or manganese
D.	All of the above
Answer» E.

Discussion

1000.	What is the typical level of change in resistance per degree change in temperature?
A.	1% to 2%
B.	3% to 5%
C.	7% to 10%
D.	10% to 25%
Answer» C. 7% to 10%

Discussion

Explore topic-wise MCQs in Engineering.

The output signal of an op-amp is ________ out of phase with its input signal connected to the inverting input terminal.

The output offset voltage is determined by ________.

In a differential connection, the signals that are opposite at the inputs are ________ amplified, and those that are common to the two inputs are ________ amplified.

What is the response time of light-emitting diodes (LEDs)?

What is the response time of LCDs?

The current capability of power diodes can be increased by placing two or more in series.

Selectivity in a receiver is provided by the resonant circuits of the IF section.

An AM signal is made up of a carrier, an upper-side frequency, and a lower-side frequency.

Frequency modulation is achieved by varying the frequency of an oscillator with a modulating signal.

A good op-amp has low voltage gain, low output impedance, and high input impedance.

A non-inverting amplifier has a higher input impedance and a lower output impedance than the op-amp itself (without feedback).

What type of temperature coefficient do thermistors have?

Which of the following diodes has a negative-resistance region?

The tuning diode is a ________-dependent, variable ________.

Inverting amplifier connection is more widely used because it has ________.

An operational amplifier is a ________ gain and ________ bandwidth differential amplifier.

The main feature of the differential amplifier is the ________ gain when opposite signals are applied to the inputs as compared to the ________ gain resulting from common inputs.

The temperature coefficient can be ________ for different Zener levels.

Introducing those impurity elements that have ________ valence electrons creates the n-type material.

The reverse-bias current ________ with the increase of temperature.

Any electron that has left its parent atom has ________ energy state relative to any electron in the atomic structure.

The diffused impurities with ________ valence electrons are called acceptor atoms.

A(n) ________ is the simplest of semiconductor devices.

The reverse-saturation current level is typically measured in ________.

The depletion width ________ in the forward bias, which results in having a majority flow across the junction.

The test current in a Zener diode IZT is the current defined by the ________ power level.

The ac resistance of a diode is the ________ of the characteristic curve at the Q-point of operation.

The potential at which the characteristics curve vertical rise occurs is commonly referred to as the ________.

The ________ the current through a diode, the ________ the dc resistance level.

The heavier the current in a Zener diode in reverse bias, ________ dynamic resistance value.

The demodulator recovers the audio signal from the IF output.

Varying the ________ can control the location of the Zener region.

The term ________ is often used when comparing the resistance level of materials.

The reverse recovery time of most commercial switching diodes is in the range of ________.

Diodes are connected ________ to increase the current-carrying capacity.

The purpose of the balanced modulator is to remove the carrier frequency.

The mixer takes the RF signal along with the audio signal to produce the IF signal.

The IF of an FM receiver operates at a center frequency of 455 kHz.

A balanced modulator is used in standard AM to obtain the sum and difference frequencies.

What metal(s) is(are) used in the construction of Schottky diodes?

What is the maximum temperature limit for liquid-crystal displays (LCDs)?

Which of the following diodes is limited to the reverse-bias region in its region of operation?

In filters, a single RC network is called a pole.

A band-pass filter passes all frequencies within a band between a lower and an upper cutoff frequency.

A second-order filter has a roll-off of 20 dB/decade.

Butterworth filters have the characteristic of a very flat response in the passband and a roll-off of 20 dB/decade.

Which of the following areas is (are) applications of varactor diodes?

This is an approximate equivalent circuit for the ________ diode.

Which of the following materials is (are) used in the manufacturing of thermistors?

What is the typical level of change in resistance per degree change in temperature?

In a differential connection, the signals that are opposite at the inputs are amplified, and those that are common to the two inputs are amplified.

The tuning diode is a -dependent, variable .

An operational amplifier is a gain and bandwidth differential amplifier.

The main feature of the differential amplifier is the gain when opposite signals are applied to the inputs as compared to the gain resulting from common inputs.

The the current through a diode, the the dc resistance level.