6.

 When PN junction is in forward bias, by

increasing the battery voltage

   A .Circuit resistance increases

   B. Current through P-N junction increases
   C .Current through P-N junction decreases
   D. None of the above happens

✔ View Answer

B. Current through P-N junction increases

7. When a PN junction is reverse-biased

A. Holes and electrons tend to concentrate

towards the junction
B. The barrier tends to break down
C. Holes and electrons tend to move away
from the junction
D. None of the above

✔ View Answer
C. Holes and electrons tend to move
away from the junction

8. In a PN junction when the applied voltage

overcomes the ........ potential, the diode current
is large, which is known as .............

A. Depletion, negative bias

B. Reverse, reverse bias
C. Resistance, reverse bias
D. Barrier, forward bias

✔ View Answer

E. Barrier, forward bias

9. A PN junction is said to be forward biased

when

A. Positive terminal of the battery is connected

to P-side and the negative side to the N-side
   B. Junction is earthed

   C.N-side is connected directly to the p-side

   D. Positive terminal of the battery is

connected to N-side and the negative side to
the P-side

 View Answer

A. Positive terminal of the battery is

connected to P-side and the negative
side to the N-side

10. A PN junction

A. Has low resistance in forward as well as

reverse directions
   B .Has high resistance in forward as well as
reverse directions
B. Conducts in forward direction only
C. Conducts in reverse direction only
✔ View Answer

D. Conducts in forward direction only

1. In a PN junction with no external voltage, the

electric field between acceptor and donor ions
is called a

A. Peak
B. Barrier
C. Threshold
D. Path

✔ View Answer

B. Barrier
2. In a PN junction the potential barrier is due
to the charges on either side of the junction,
these charges are

A. Majority carriers
B. Minority carriers
 C. Both (a) and (b)
D. Fixed donor and acceptor ions

✔ View Answer

D Fixed donor and Acceptor ions

3. The capacitance of a reverse biased PN

junction

A. Increases as reverse bias is increased

B. Decreases as reverse bias is increased
C. Increases as reverse bias is decreased
D. Is insignificantly low

✔ View Answer

C. Increases as reverse bias is

decreased

4. In an unbiased PN junction

 A. The junction current is due to minority
carriers only
B. The junction current at equilibrium is zero as
equal but opposite carriers are crossing the
junction
C. The junction current reduces with rise in
temperature
D. The junction current at equilibrium is zero as
charges do not cross the junction

✔ View Answer

B. The junction current at equilibrium is

zero as equal but opposite carriers are
crossing the junction
5. For a PN junction diode, the current in
reverse bias may be

A. Few miliamperes
B. Between 0.2 A and 15 A
C. Few amperes
D. Few micro or nano amperes

✔ View Answer
 D Few micro or nano amperes

11. PN junction failure below 5 V is caused

primarily by

A. Avalanche breakdown
B. Zener breakdown
C. Either of (a) and (b) above
D. None of the above

✔ View Answer

B. Zener breakdown

12. As a PN junction is forward biased

A. Holes as well as electrons tend to drift away

from the junction
B. The depletion region decreases
C. The barrier tends to breakdown
D. None of the above

✔ View Answer
B. The depletion region decreases

13. In a reverse biased PN junction, the current

through the junction increases abruptly at

   A.0.5 V
   B.1.1 V
   C.0.72 V
E. Breakdown voltage

✔ View Answer

E. Breakdown voltage

14. The main reason why electrons can tunnel

through a PN junction is that

A. Barrier potential is very low

B. They have high energy
C. Impurity level is low
D. Depletion layer is extremely thin
✔ View Answer

E. Depletion layer is extremely thin

15. A PN junction is formed in a process which

may be of

A. Diffused type
   B. Alloyed type
B. The grown type
C. Any of the above

✔ View Answer

D. Any of the above

16. A reverse-biased PN junctions has

   A.A net electron current

   B.A net hole current
   C.A very narrow depletion layer
E. Almost zero current

✔ View Answer

F. Almost zero current

17. The depletion layer of a PN junction diode

has

A. Only free mobile holes

B. Only free mobile electrons
C. Both free mobile holes as well as electrons
D. Neither free mobile electrons nor holes

D. Neither free mobile electrons nor holes

18. The depletion region of a PN junction is one
that is depleted of

A. Immobile charges
B. Mobile charges
C. Atoms
D. None of the above

B. Mobile charges

19. The potential barrier existing across a PN

junction corresponds to

  
A. Width of the barrier
B. Reverse bias of the junction
C. Forward bias of the junction
D. Height of the barrier
✔ View Answer

E. Height of the barrier

20. Mobile electrons of P-side of the PN
junction diode constitute

A. Minority current carriers

B. Majority current carriers
C. Depending upon voltage they may be either
majority or minority current carriers
D. None of the above

✔ View Answer

A. Minority current carriers

21. When a PN junction is reverse biased

A. Holes and electrons move away from the

junction
B. Depletion region decreases
C. Movement of holes and electrons is seized
D. Holes and electrons move towards the
junction
✔ View Answer

A. Holes and electrons move away from

the junction

22. When a PN junction is reverse biased

A. Reverse current flow ceases

   B.A very small amount of reverse current
called leakage current flows
B. Heavy current flow in the reverse circuit
E. All of the above

✔ View Answer

B.A very small amount of reverse current

called leakage current flows

23. For a PN junction, the junction current will

be zero when

A. The two junctions are short circuited

B. Holes and electrons get neutralized by
equal numbers
 C. The number of minority carriers crossing the
junction equals the number of majority
carriers
D. Either minority carriers or majority carriers
disappear

✔ View Answer

C.The number of minority carriers

crossing the junction equals the
number of majority carriers

24. A reversed-biased PN junction has

A. Almost zero current

   B.A very narrow depletion layer
   C.A net hole current
   D.A net electron current

✔ View Answer

A. Almost zero current

25. Barrier potential in a PN junction is caused
by

A. Flow of drift current

B. Diffusion of majority carriers across the
junction
C. Migration of minority carriers across the
junction
D. Thermally-generated electrons and holes

✔ View Answer

B. Diffusion of majority carriers across

the junction

26. The diode used for a power limiter is

A. Power diode
B. Zener diode
C. PIN diode
D. Signal diode
✔ View Answer

C.PIN diode

27. The diode which is preferred for D.C

coupling is

   A.LED
   B. Power diode
C. Signal diode
D. Zener diode

✔ View Answer

E. Zener diode

28. The diode which permits remote tuning is

A. Zener diode
B. Varactor
C. Power diode
D. None of the above

✔ View Answer
 B.Varactor

29. The diode is used in

A. Digital circuits
B. Detectors
C. Rectifiers
   D .All of the above

✔ View Answer

D. All of the above

30. The dynamic resistance of a diode varies as

   A.1/I2
   B.I2
   C.1/I
   D.I the current

✔ View Answer

C.1/I
31. The static VI characteristics of a junction
diode can be described by the equation called

   A .Child's three half-power law

C. Boltzmann diode equation
D. Einstein's photoelectric equation
E. Richardson-Dushman equation

✔ View Answer

B. Boltzmann diode equation

32. In case of alloy junction diode, the width of

depletion layer 'w' is proportional to

A. Cube of reverse voltage

B. Square root of reverse voltage
C. Cube root of reverse voltage
D. Square of reverse voltage

✔ View Answer
 C. Square root of reverse voltage

33. The space charge region in a junction diode

contains charges that are

A. Fixed donor and acceptor ions

B. Majority carriers only
C. Minority carriers only
D. Mobile donor and acceptor ions

✔ View Answer

A. Fixed donor and acceptor ions

34. The reverse saturation current in junction

diode is independent of

A. Potential barrier
B. Junction area
C. Doping of 'P' and 'N' type region
D. Temperature

✔ View Answer
 B. Junction area

35. When reverse bias is applied to a junction

diode

A. Potential barrier is lowered

B. Majority carrier current is increased
C. Minority carrier current is increased
D. Potential barrier is raised

✔ View Answer

E. Potential barrier is raised

41. In a Zener diode with high breakdown

voltage

A. Both P and N are heavily doped

B. Both P and N are lightly doped
C. Either P or N is lightly doped
D. None of the above
✔ View Answer

b. Both P and N are lightly doped

42. In Zener diode, the Zener breakdown takes

place

A. Above 6 V
B. Below 6 V
C. At 6 V
D. None of the above

✔ View Answer

C. Below 6 V

43. The current in a Zener diode is controlled by

A. Zener diode resistance

B. Potential barrier
C. Reverse bias voltage
D. External circuits
✔ View Answer

E. External circuits

44. A zener diode when biased correctly

A. Acts as a fixed resistance

B. Never overheats
C. Has a constant voltage across it
D. Has a constant current passing through it

✔ View Answer

D. Has a constant voltage across it

\

45. In Zener diode, the breakdown is due to

Zener, has doping

A. Lowest
B. Moderate
C. High
D. Low
✔ View Answer

D. High

46. In a zener diode

A. Negative resistance characteristic exists

B. Forward voltage rating is high
C. Sharp breakdown occurs at low reverse
voltage
D. All of the above

✔ View Answer

D. Sharp breakdown occurs at low reverse

voltage

47. Depletion region contains

 A. Free holes
B. Free electrons
C. Immobile charge carriers
D. All of the above

✔ View Answer

B. Immobile charge carriers

48. Depletion region behaves as

A. Semiconductor
B. An insulator
C. Conductor
D. High resistance

✔ View Answer

C. An insulator

49. Holes are available in

A. Valence band
B. Forbidden gap
C. Conduction band
 D. None of the above

✔ View Answer

A. Valence band

50. Odd out the following :

A. Tunnel diode
B. Vacuum triode
C. Backward diode
D. Gunn diode

✔ View Answer

B. Backward diode

21. The biasing circuit has a stability factor of

50. If due to temperature change, ICBO changes
by 1 μA, then IC will change by __________
A. 100μA
 B.25 μA
C. 20 μA
D. 50 μA
View answer
Correct answer: (D)
50 μA
22. The circuit that provides the best
stabilization of operating point is __________
A. Base resistor bias
B.Collector feedback bias
C. Potential divider bias
D. None of the above
View answer
Correct answer: (C)
Potential divider bias
23. The disadvantage of base resistor method
of transistor biasing is that it __________
A. Is complicated
B.Is sensitive to changes in β
 C. Provides high stability
D. None of the above
View answer
Correct answer: (B)
Is sensitive to changes in β
24. The disadvantage of voltage divider bias is
that it has __________.
A. High stability factor
B.Low base current
C. Many resistors
D. None of the above
View answer
Correct answer: (C)
Many resistors
25. The leakage current in a silicon transistor is
about __________ the leakage current in a
germanium transistor
A. One hundredth
B.One tenth
 C. One thousandth
D. One millionth
View answer
Correct answer: (C)
One thousandth
26. The operating point __________ on the a.c.
load line
A. Also line
B.Does not lie
C. May or may not lie
D. Data insufficient
View answer
Correct answer: (A)
Also line
27. The operating point is also called the
__________.
A. Cut off point
B.Quiescent point
C. Saturation point
 D. None of the above
View answer
Correct answer: (B)
Quiescent point
28. The point of intersection of d.c. and a.c. load
lines represents __________
A. Operating point
B.Current gain
C. Voltage gain
D. None of the above
View answer
Correct answer: (A)
Operating point
29. The purpose of resistance in the emitter
circuit of a transistor amplifier is to __________.
A. Limit the maximum emitter current
B.Provide base-emitter bias
C. Limit the change in emitter current
D. None of the above
View answer
Correct answer: (C)
Limit the change in emitter current
30. The stabilization of operating point in
potential divider method is provided by
__________
A. RE consideration
B.RC consideration
C. VCC consideration
D. None of the above
View answer
Correct answer: (A)
RE consideration
 1.Clipping is the result of
A. The input signal being too large.
B. The transistor being driven into saturation.
C. The transistor being driven into cutoff.
D. all of the above
Answer: Option D

2. Which transistor bias circuit arrangement provides

good stability using negative feedback from
collector to base?
A. base bias
B. collector-feedback bias
C. voltage-divider bias
D. emitter bias
Answer: Option B
Q1. A transistor has …………………
1. One pn junction
2. Two pn junctions
3. Three pn junctions
4. Four pn junctions
Answer: 2
Q2. The number of depletion layers in a
transistor is …………
1. Four
2. Three
3. One
4. Two
Answer: 4
Q3. The base of a transistor is ………….. doped

1. Heavily
2. Moderately
3. Lightly
4. None of the above
Answer: 3
Q4. The element that has the biggest size in a
transistor is ………………..

1. Collector
2. Base
3. Emitter
4. collector-base-junction
Answer: 1
Q5. In a pnp transistor, the current carriers are
………….
1.Acceptor ions
2.Donor ions
3.Free electrons
4.Holes
Answer: 4
Q6. The collector of a transistor is ………….
doped
1. Heavily
2. Moderately
3. Lightly
4. None of the above
Answer: 2
Q7. A transistor is a …………… operated device

1. Current
2. Voltage
3. Both voltage and current
4. None of the above

Answer: 1
Q8. In a npn transistor, are the minority carriers
1. Free electrons
2. Holes
3. Donor ions
4. Acceptor ions
Answer: 2

Q9. The emitter of a transistor is …………………

doped
1. Lightly
2. Heavily
3. Moderately
4. None of the above
Answer: 2

Q10. In a transistor, the base current is about

………….. of emitter current1. 1 25%
2. 20%
3. 35 %
4. 5%
Answer: 4
Q11. At the base-emitter junctions of a transistor,
one finds ……………
1. a reverse bias
2. a wide depletion layer
3. low resistance
4. none of the above
Answer : 3
Q12. The input impedance of a transistor is
………….
1. High
2. Low
3. Very high
4. Almost zero
Answer: 2
Q13. Most of the majority carriers from the
emitter ………………..
1. Recombine in the base
2. Recombine in the emitter
3. Pass through the base region to the collector
4. none of the above
Answer :3
Q14. The current IB is …………
1. electron current
2. hole current
3. donor ion current
4. acceptor ion current
Answer : 1
Q15. In a transistor ………………..IC = IE + IB
IB = IC + IE
IE = IC – IB
IE = IC + IB
Answer : 4
16. The value of α of a transistor is ……….
1, more than 1
2, less than 1
3, 1
4, none of the above
Answer : 2

17. IC = αIE + ………….

1. IB
2. ICEO
3. ICBO
4. βIB
Answer : 3

18. The output impedance of a transistor is

……………..
1. high
2. zero
3. low
4. very low
Answer : 1

19. In a transistor, IC = 100 mA and IE = 100.2

mA. The value of β is
…………
1. 100
2. 50
3. about 1
4. 200
Answer : 4

20. In a transistor if β = 100 and collector current

is 10 mA, then IE is
…………
1. 100 mA
2. 100.1 mA
3. 110 mA
4. none of the above
Answer : 2

21. The relation between β and α is …………..

1. β = 1 / (1 – α )
2. β = (1 – α ) / α
3. β = α / (1 – α )
4. β = α / (1 + α )
Answer : 3

22. The value of β for a transistor is generally

………………..
1. 1
2. less than 1
3. between 20 and 500
4. above 500
Answer : 3

23. The most commonly used transistor

arrangement is ……………

1. common emitter
2. common base
3. common collector
4. none of the above
Answer : 1

24. The input impedance of a transistor

connected in ……………..
arrangement is the highest
1. common emitter
2. common collector3. common base
4. none of the above
Answer : 2

25. The output impedance of a transistor

connected in …………….
arrangement is the highest
1. common emitter
2. common collector
3. common base
4. none of the above
Answer : 3

26. The phase difference between the input and

output voltages in a
common base arrangement is …………….
1. 180o
2. 90o
3. 270o
4. 0o
Answer : 4

27. The power gain in a transistor connected in

……………. arrangement
is the highest
1. common emitter
2. common base
3. common collector
4. none of the above
Answer : 1

28. The phase difference between the input and

output voltages of a
transistor connected in common emitter
arrangement is ………………
1. 0o
2. 180o
3. 90o
4. 270o
Answer : 2

29. The voltage gain in a transistor connected in

……………….
arrangement is the highest
1. common base
2. common collector
3. common emitter
4. none of the above
Answer : 3

30. As the temperature of a transistor goes up,

the base-emitter resistance
……………
1. decreases
2. increases
3. remains the same
4. none of the above
Answer : 1
31. The voltage gain of a transistor connected in
common collector
arrangement is ………..
1. equal to 1
2. more than 10
3. more than 100
4. less than 1
Answer : 4

32. The phase difference between the input and

output voltages of a
transistor connected in common collector
arrangement is ………………
1. 180o
2. 0o
3. 90o
4. 270o
Answer : 2

33. IC = β IB + ………..
1. ICBO
2. IC
3. ICEO
4. αIE
Answer : 3

34. IC = [α / (1 – α )] IB + ………….
1. ICEO
2. ICBO
3. IC
4. (1 – α ) IB
Answer : 1

35. IC = [α / (1 – α )] IB + […….. / (1 – α )]
1. ICBO
2. ICEO
3. IC
4. IE
Answer : 1

36. BC 147 transistor indicates that it is made of

…………..
1. germanium
2. silicon
3. carbon
4. none of the above
Answer : 2
Q37. ICEO = (………) ICBO
1. β
2. 1 + α
3. 1 + β
4. none of the above
Answer : 3

38. A transistor is connected in CB mode. If it is

not connected in CE
mode with same bias voltages, the values of IE, IB
and IC will …………..
1. remain the same
2. increase3. decrease
4. none of the above
Answer : 1

39. If the value of α is 0.9, then value of β is

………..
1. 9
2. 0.9
3. 900
4. 90
Answer : 4

40. In a transistor, signal is transferred from a

…………… circuit
1. high resistance to low resistance
2. low resistance to high resistance
3. high resistance to high resistance
4. low resistance to low resistance
Answer : 2
Q41. The arrow in the symbol of a transistor
indicates the direction of
………….
1. electron current in the emitter
2. electron current in the collector
3. hole current in the emitter
4. donor ion current
Answer : 3

42. The leakage current in CE arrangement is

……………. that in CB
arrangement
1. more than
2. less than
3. the same as
4. none of the above
Answer : 1
43. A heat sink is generally used with a transistor
to …………1. increase the forward current
2. decrease the forward current
3. compensate for excessive doping
4. prevent excessive temperature rise
Answer : 4

44. The most commonly used semiconductor in

the manufacture of a
transistor is ………….
1. germanium
2. silicon
3. carbon
4. none of the above
Answer : 2

45. The collector-base junction in a transistor has

……………..
1. forward bias at all times
2. reverse bias at all times
3. low resistance
4. none of the above
Answer : 2
46. When transistors are used in digital circuits
they usually operate in
the ………….
1. active region
2. breakdown region
3. saturation and cutoff regions
4. linear region
Answer : 3

47. Three different Q points are shown on a dc

load line. The upper Q
point represents the ………….
1. minimum current gain
2. intermediate current gain
3. maximum current gain
4. cutoff point
Answer : 3

48. A transistor has a

of 250 and a base current, IB, of 20 A. The
collector current, IC, equals to …………….
1. 500 μA
2. 5 mA
3. 50 mA
4. 5 A
Answer : 2

49. A current ratio of IC/IE is usually less than

one and is called …………
1. beta
2. theta
3. alpha
4. omega
Answer : 3

50. With the positive probe on an NPN base, an

ohmmeter reading
between the other transistor terminals should be
……
1. open
2. infinite
3. low resistance
4. high resistance
Answer : 3

51. In a CE configuration, an emitter resistor is

used for ……
1. stabilization
2. ac signal bypass
3. collector bias
4. higher gain
Answer : 1

52. Voltage-divider bias provides ……….

1. an unstable Q point
2. a stable Q point
3. a Q point that easily varies with changes in the
transistor’s current gain4. a Q point that is stable and
easily varies with changes in the transistor’s
current gain
Answer : 2

53. To operate properly, a transistor’s base-

emitter junction must be
forward biased with reverse bias applied to which
junction?
1. collector-emitter
2. base-collector
3. base-emitter
4. collector-base
Answer : 4

54. The ends of a load line drawn on a family of

curves determine ……
1. saturation and cutoff
2. the operating point
3. the power curve
4. the amplification factor
Answer : 1
55. If VCC = +18 V, voltage-divider resistor R1 is
4.7 k , and R2 is 1500 ,
then the base bias voltage is ……….
1. 8.7 V
2. 4.35 V
3. 2.9 V
4. 0.7 V
Answer: 2

56. The C-B configuration is used to provide

which type of gain?
1. voltage
2. current
3. resistance
4. power
Answer : 1

57. The Q point on a load line may be used to

determine …………1. VC
2. VCC
3. VB
4. IC
Answer : 3
58. A transistor may be used as a switching
device or as a ………….
1. fixed resistor
2. tuning device
3. rectifier
4. variable resistor
Answer : 4

59. If an input signal ranges from 20–40 A (micro

amps), with an output
signal ranging from .5–1.5 m (milliamps), what is
the ac beta?
1. 0.05
2. 20
3. 50
4. 500
Answer : 3
Q60. Beta’s current ratio is ……..
1. IC/IB
2. IC/IE
3. IB/IE
4. IE/IB
Answer: 1
61. A collector characteristic curve is a graph
showing ………..
1. emitter current (IE) versus collector-emitter
voltage (VCE) with (VBB) base
bias voltage held constant
2. collector current (IC) versus collector-emitter
voltage (VCE) with (VBB)
base bias voltage held constant
3. collector current (IC) versus collector-emitter
voltage (VC) with (VBB)
base bias voltage held constant4. collector current
(IC) versus collector-emitter voltage (VCC) with
(VBB)
base bias voltage held constant
Answer: 2

62. With low-power transistor packages, the base

terminal is usually the
……….
1. tab end
2. middle
3. right end
4. stud mount
Answer: 2
Q63. When a silicon diode is forward biased,
VBE for a CE configuration is
……..
1. voltage-divider bias
2. 0.4 V
3. 0.7 V
4. emitter voltage
Answer: 3

64. What is the current gain for a common-base

configuration where IE =
4.2 mA and IC = 4.0 mA?
1. 16.8
2. 1.05
3. 0.2
4. 0.95
Answer: 4

65. With a PNP circuit, the most positive voltage

is probably …………
1. ground
2. VC
3. VBE
4. VCC
Answer: 1

66. If a 2 mV signal produces a 2 V output, what

is the voltage gain?1. 0.001
2. 0.004
3. 100
4. 1000
Answer: 4

67. Most of the electrons in the base of an NPN

transistor flow …………
1. out of the base lead
2. into the collector
3. into the emitter
4. into the base supply
Answer: 2
Q68. In a transistor, collector current is
controlled by ………..
1. collector voltage
2. base current
3. collector resistance
4. all of the above
Answer: 2

69. Total emitter current is …………

1. IE – IC
2. IC + IE
3. IB + IC
4. IB – IC
Answer: 3

70. Often a common-collector will be the last

stage before the load; the
main function(s) of this stage is to ………….
1. provide voltage gain
2. provide phase inversion
3. provide a high-frequency path to improve the
frequency response
4. buffer the voltage amplifiers from the low-
resistance load and provide
impedance matching for maximum power transfer
Answer: 4
Q71. For a CC configuration to operate properly,
the collector-base
junction should be reverse biased, while forward
bias should be applied to
…………… junction.
1. collector-emitter
2. base-emitter
3. collector-base
4. cathode-anode
Answer: 1
Q72. The input/output relationship of the
common-collector and common
base amplifiers is ………..
1. 270 degrees
2. 180 degrees
3. 90 degrees
4. 0 degrees
Answer: 4
Q73. If a transistor operates at the middle of the
dc load line, a decrease in
The current gain will move the Q point ………….
1. off the load line
2. nowhere
3. up
4. down
Answer: 4

74. Which is the higher gain provided by a CE

configuration?
1. voltage
2. current
3. resistance
4. power

Answer: 4Q75. What is the collector current for a

CE configuration with a beta of
100 and a base current of 30 A?
1. 30 A
2. 0.3 A
3. 3 mA
4. 3 MA
Answer: 3
Q1
The three terminals of a bipolar junction
transistor are called
A) p ,n ,p
B) n, p, n
C) input, output, ground
D) base, collector, emitter

Q2.
In a PNP transistor, the P regions are

A) base and emitter

B) base and collector
C) emitter and collector
D) all of the above
Q3.
For operation as an amplifier, the base of an NPN
transistor must be
Ans:-
A) positive with respect to the emitter
B) negative with respect to the emitter
C) positive with respect to the collector
D) 0 V

Q4.
The emitter current is always
A) greater than the base current
B) less than the collector current
C) greater than the collector current
D) greater than the base current and greater than
the collector
current

Q5.
The βdc of a transistor is its
A) current gain
B) voltage gain
C) power gain
D) internal resistanceQ6.
If Ic is 50 times larger than IB, then βDC

A) 0.02
B) 100
C) 50
D) 500

Q7.
The approximate voltage across the forward-
biased base-emitter junction
of a silicon BJT is

A) 0 V
B) 0.7 V
C) 0.3 V
D) VBB
Q8.
The bias condition for a transistor to be used as a
linear amplifier is called
(mark1)
A) forward-reverse
B) forward-forward
C) reverse-reverse
D) collector bias
Q9.
If the output of a transistor amplifier is 5 V rms
and the input is 100 mV
rms, the voltage gain is

A) 5
B) 500
C) 50
D) 100

Q10.
When operated in cut-off and saturation, the
transistor acts like a

A) linear amplifier
B) switch
C) variable capacitor
D) variable resistor

Q11.
In cut-off, VCE is
A) Minimum
B) B) maximum
C) equal to Vcc
D) maximum and equal to Vcc

Q12.
In saturation , VCE is

A) 0.7 V
B) equal to VCC
C) minimum
D) maximum

Q13.
To saturate a BJT,
A) IB=IC(sat)
B) I B >IC(sat)/ βDC
C) VCC must be at least 10 V
D) the emitter must be grounded

Q14.
Once in saturation, a further increase in base
current will
A) cause the collector current to increase
B) not affect the collector current
C) cause the collector current to decease
D) turn the transistor off
Q15.
If the base emitter junction is open, the collector
voltage is
A) VCC
B) 0 V
C) Floating
D) 0.2 V

Q16.
A small-signal amplifier
A) uses only a small portion of its load line
B) always has an output signal in the mV range
C) goes into saturation once on each input cycle
D) is always a common-emitter amplifierQ17.
The parameter hfe corresponds to
A) βDC
B) βac
C) re’
D) rc’

Q18.
The circuit that provides the best stabilization of
operating point is..........
A) base resistor bias
B) collector feedback bias
C) potential divider bias
D) none of the above
Q19.
A certain common emitter amplifier has a voltage
gain of 100. If the emitter
bypass capacitor is removed
A) the circuit will become unstable
B) the voltage gain will decrease
C) the voltage gain will increase
D) the Q-point will shift

Q21.
A heat sink is generally used with a transistor
to.........
A) increase the forward current
B) decrease the forward current
C) compensate for excessive doping
D) prevent excessive temperature rise

Q22.
For a common emitter amplifier, RC=1.0KΩ,
RE=390Ω, βac=75, re’=15.
Assuming that RE is completely bypassed at the
operating frequency, the
voltage gain is
A) 66.7
B) 2.56
C) 2.47
D) 75

Q23.
Which is the higher gain provided by a C-E
configuration?
A) Voltage
B) Current
C) Resistance
D) Power

Q24.
In a transistor, signal is transferred from
a ........circuit.
A) high resistance to low resistance
B) high resistance to high resistance
C) low resistance to high resistance
D) low resistance to low resistance

Q25.
The input resistance of a common-base amplifier
is
A) very low
B) very high
C) the same as CE
D) the same as CC

Q26.
In a common-emitter amplifier with voltage
divider bias, Rin(base)=68 kΩ,
R1=33kΩ and R2=15kΩ. The total input
resistance is

A) 68 kΩ
B) 8.95 kΩ
C) 22.2 kΩ
D) 12.3 kΩ

Q27.
A CE amplifier is driving a 10kΩ load. If Rc=2.2 kΩ
and re’=10 Ω, the voltage
gain is approximately

A) 220
B) 1000
C) 10
D) 180

Q28.
Each stage of a four-stage amplifier has a voltage
gain of 15. The overall
voltage gain is
A) 60
B) 15
C) 50,625D) 3078

Q29.
In the common-emitter configuration, if the
transistor is in the active
region, then

A) Ic = β IE
B) IE = α IB
C) IB = β Ic
D) Ic= β IB

Q30. In the common-emitter configuration, if the

transistor is in the saturation
region, then
A) IC>IE
B) IC< β IB
C) IE< IB
D) IB> β IC

Q31.
The emitter of a transistor is..........doped.
A) Moderately
B) Heavily
C) Lightly
D) none of the above

Q32.

A transistor is a ...........operated device.

A) current and voltage
B) current
C) voltage
D) resistor

Q33.
The input impedance of a transistor is.....

A) low
B) high
C) very high
D) mediu

mQ34.
The output impedance of a transistor is
A) low
B) high
C) very low
D) none of the above

Q35.
The relation between β and α is........
A) β = α/1+α
B) β = α/1-α
C) β = α -1/α
D) β = α+1/α

Q36.
The value of β of a transistor is ............
A) between 20 and 500
B) 1
C) less than 1
D) 0

Q37.
Transistor biasing represents .........condition
A) a.c
B) d.c
C) both a.c. and d.c.
D) none of above

Q38.
Transistor biasing is generally provided by a.........
A) biasing circuit
B) bias battery
C) Diode
D) a.c. input
Q49.
The point of intersection of d.c and a.c load lines
represents.......
A) current point
B) operating point
C) voltage gain
D) power point

Q40.
The phase difference between the input and
output voltage in common
base arrangements is....
A) 900
B) 1800
C) 0
D) 3600

Q41.
The phase difference between the input and
output voltage in common
emitter arrangements is.....

A) 0
B) 90
C) 180
D) 270

Q42.
In the zero signal conditions, a transistor sees ......
A) a.c
B) a.c and d.c
C) d.c
D) operating point

Q43.
The input capacitor in an amplifier is the .......
capacitor.
A) bypass
B) coupling
C) leakage
D) emitter

Q44.
The point of intersection of d.c and a.c load lines
called.

A) cut off point

B) operating point
C) saturation point
D) none of above
Q45.
In the d.c equivalent circuit of a transistor
amplifier, the capacitor is
considered.....
A) short
B) open
C) open and short
D) switch

Q46.
In practice, the voltage gain of an amplifier is
expressed.......
A) in db
B) in volts
C) in numbers
D) in watts
Q47.
The purpose of d.c conditions, in a transistor is
to...
A) reverse bias the emmiter
B) set up operating point
C) reverse bias the collector
D) forward bias base

Q48.
A transistor amplifier has high output impedence
because.....
A) high efficiency
B) emitter is heavily doped
C) collector has reverse bias
D) base-emitter junction forward biased

Q49.
The noise factor of an ideal amplifier expressed in
db is-----
A) 1
B) 0
C) 0.1
D) 10

Q50.
The gain of an amplifier is expressed in db
because..........
A) human ear response is logarithmic
B) it is simple unit
C) calculation easy
D) easy to understand

Q51.
In a BJT with β= 100, ‘α’ equals

A) 99
B) 0.99
C) 1.0
D) 1.01

Q52.
Pinch-off voltage VP for an FET is the drain
voltage at which

A) significant drain current starts flowing

B) drain current becomes zero
C) all free charges get removed from the channel
D) avalanche break down takes place

Q53.

A transistor in common emitter mode has

A) a high input resistance and low output
resistance
B) a medium input resistance and high output
resistance
C) a very low input resistance and a low output
resistance
D) a high input resistance and a high output
resistance

Q54.
Compared to bipolar transistor, a JFET has
A) lower input impedance
B) higher voltage gain
C) higher input impedance and high voltage gain
D) higher input impedance and low voltage gain

Q55.
JFET is a
A) Current controlled device with high input
resistance
B) Voltage controlled device with high input
resistance
C) Current Controlled Current Source (CCCS)
D) Voltage Controlled Voltage Source (VCVS)

Q56.
Which of the following is an active device
A) an electric bulb
B) B) a diode
C) a BJT
D) a transformer
57. Which configuration has unity voltage gain
(ideal)
A) a Common Collector (CC)
B) a Common Emitter (CE)
C) a Common Base (CB)
D) CE followed by CB
58. Removing bypass capacitor across the
emitter-leg resistor in a CE amplifier
causes
A) increase in current gain
B) decrease in current gain.
C) increase in voltage gain.
D) decrease in voltage gain.

Q59.
The important characteristic of emitter-follower
is
A) high input impedance and high output
impedance
B) high input impedance and low output
impedance
C) low input impedance and low output
impedance
D) low input impedance and high output
impedance

60. In a JFET, at pinch-off voltage applied on the

gate
A) the drain current becomes almost zero
B) the drain current begins to decrease
C) the drain current is almost at saturation value.
D) the drain-to-source voltage is close to zero
volts.

61. The common collector amplifier is also known

as
A) collector follower
B) Base follower
C) Emitter follower
D) Source follower

62. Transistor is a
A) Current controlled current device
B) Current controlled voltage device
C) Voltage controlled current device
D) Voltage controlled voltage device

63. For a JFET, when VDS is increased beyond the

pinch off voltage, the drain
current
A) Increases
B) Decreases
C) remains constant.
D) First decreases and then increases.
64. Two stages of BJT amplifiers are cascaded by
RC coupling. The voltage gain
of the first stage is 10 and that of the second stage
is 20. The overall gain of
the coupled amplifier is
A) 10x20
B) 10+20
C) (10+20)2
D) (10x20)/2
66. The current amplification factor in CE
configuration is
A) Β
B) Α
C) β+1D) 1/ β

67. The arrowhead on the transistor symbol

points in the direction of
A) The arrowhead on the transistor symbol
points in the direction of
B) minority carrier flow in the emitter region.
C) majority carrier flow in the remitter region.
D) Conventional current flow in the emitter
region.
68. The silicon transistor are more widely used
than germanium transistors
because
A) they have smaller leakage current
B) they have better ability to dissipate heat
C) they have smaller depletion layer
D) they have larger current carrying capacity

69. For an NPN transistor in normal bias

A) only holes cross the collector junction
B) only majority carriers cross the collector
junction
C) the emitter junction has high resistance
D) emitter junction is forward biased and
collector junction is
reverse biased

70. The most commonly used transistor circuit

arrangement is
A) common base
B) common emitter
C) common collector
D) none of these

71. For transistor action

A) The base region must be very thin and lightly
doped.
B) the emitter junction must be forward biased
and collector junction
should be reverse biased.
C) the emitter should be heavily doped to supply
the required amount
of majority carriers.
C) all of these

72. The ICBO is the current that flows when some

dc voltage is applied
A) in the forward direction to the emitter
junction with collector open
B) in the reverse direction to the emitter junction
with collector open
C) in the reverse direction to the collector
junction with emitter
open
D) in the forward direction to the collector
junction with emitter open

73. The magnitude of current ICBO

A) depends largely upon the emitter doping
B) depends largely upon emitter-base junction
base potential
C) Increases with the increase in temperature
D) is generally greater in silicon than in
germanium transistor

74. The current ICBO flows in the

A) emitter and base leads
B) collector and base leads
C) emitter and collector leads
D) none of these

75. In CE mode of transistor, the most noticeable

effect of a small increase in
temperature is
A) the increase in output resistance
B) the increase in leakage current ICEO
C) the decrease in current gain
D) the increase in ac current gain

76. In CE configuration, the output V-I

characteristics are drawn by taking

A) VCE versus IC for constant value of IE

B) VBE versus IE for constant value of VCE
C) VBE versus IB for constant value of IC
D) VBE versus IB for constant value of VCE
77. The emitter current in a junction with normal
bias
A) is almost equal to the base current
B) B) is equal to the sum of IB and IC
C) is equal to the sum of IB and IC
D) is equal to ICBO

77. The β of a transistor may be determined

directly from the curve plotted
between
A) VCE and IC for constant IB
B) VCE and IC for constant IE
C) VCE and IE for constant IB
D) VBE and IE for constant VCE

78. In CB configuration, the output V-I

characteristics of a transistor are drawn
by taking
A) VCB versus IC for constant IE
B) VCB versus IB for constant IE
C) VCE versus IC for constant IE
D) VCB versus IB for constant IE
79. In which mode of BJT operation are both
junction reverse biased
A) Active
B) Saturation
C) cut off
D) reverse active

80. In which mode of BJT operation are both

junction forward biased
A) active
B) saturation
C) cut off
D) reverse active

81. In a bipolar junction transistor the base

region is made very thin so that
A) recombination in base region is minimum
B) electric field gradient in base is high
C) electric field gradient in base is highD) base
can be easily biased
82. MOSFET uses the electric field of
A) gate capacitance to control the channel
current
B) barrier potential of p-n junction to control the
channel current
C) gate capacitance to control the channel current
and barrier
potential of p-n junction to control the channel
current
D) none of these
83. In MOSFET devices the N-channel type is
better the P-channel type in the
following respects
A) it has better noise immunity
B) it is faster
C) it is TTL compatible
D) it has better drive capability
85. A depletion MOSFET differs from a JFET in the
sense that it has no

A) Channel
B) P-N junction
C) Gate
D) Substrate

86. The extremely high input impedance of a

MOSFET is primarily due to the
A) absence of its channel
B) negative gate-source voltage
C) depletion of current carriers
D) extremely small leakage current of its gate
capacitor
87. Most small-signal E-MOSFETs are found in
A) Heavy-current applications
B) Discrete circuits
C) Disk drives
D) Integrated circuit
88. The main advantage of CMOS is its

A) High power rating

B) Small-signal operation
C) Switching capability
D) Low power consumption
89. In an Enhancement MOSFET, drain current
starts only when VGS (th) is
A) Positive
B) Negative
C) Zero
D) greater than Vgs (th)
Q90.
CMOS stands for
A) Common MOS
B) Active-load switching
C) p-channel and n-channel devices
D) complementary MOS
91. Ideally, a load line is a straight line drawn on
the collector characteristic
curves between
A) the Q-point and cut-off
B) the Q-point and saturation
C) VCE(cutoff) and IC(sat)
D) IB = 0 and IB = Ic/βDC
92. Determine whether the transistor in Figure
below is biased in cutoff,
saturation, or the linear region. Keep in mind that
Ic = β DC .lB is valid only in
the linear region.
A) Cutoff
B) saturation
C) linear
D) none of these

93. The primary function of the bias circuit is to

A) hold the circuit stable at VCC
B) hold the circuit stable at Vin
C) ensure proper gain is achieved
D) hold the circuit stable at the designed Q-point
94. A certain common-emitter amplifier has a
voltage gain of 100. If the
emitter bypass capacitor is removed,
A) the circuit will become unstable
B) the voltage gain will decrease
C) the voltage gain will increase
D) the Q-point will shift

95. What is the effect on channel current, on

application of a more positive voltage to
the GATE of the depletion mode n-channel MOSFET
(true/false)
A) Reduces
B) Rises
C) Remains same
D) Can not predict

96. The input resistance of a common-base

amplifier is
(mark1)
Ans:-
A) very low
B) very high
C) the same as CE
D) the same as CC
97. When transistors are used in digital circuits
they usually operate in the:
A) active region
B) breakdown region
C) saturation and cutoff regions
D) linear region

98. Three different Q points are shown on a dc

load line. The upper Q point
represents the:
A) minimum current gain
B) intermediate current gain
C) maximum current gain
D) cut-off point

99. In a bipolar junction transistor the base region is

made very thin so that
100.
A) recombination in base region is minimum
B) electric field gradient in base is high
C) base can be easily fabricated
D) base can be easily biased
100. A current ratio of IC/IE is usually less than
one and is called:
A) Beta
B) Theta
C) Alpha
D) Omega

101. In a C-E configuration, an emitter resistor is

used for

A) Stabilization
B) ac signal bypass
C) collector bias
D) higher gain

102. The ends of a load line drawn on a family of

curves determine:
A) saturation and cutoff
B) the operating point
C) the power curve
D) the amplification factor
Q103. Often a common-collector will be the last
stage before the load; the main
function(s) of this stage is to:
(mark1)
Ans:-
A) provide voltage gain
B) provide phase inversion
C) provide a high-frequency path to improve the
frequency response
D) buffer the voltage amplifier from the low-
resistance load and
provide impedance matching for maximum
power transfer
Q104. The arrowhead on the transistor symbol
points in the direction of
(mark1)
Ans:-
A) electron flow in the emitter region.
B) minority carrier flow in the emitter region.
C) majority carrier flow in the remitter region.
D) Conventional current flow in the emitter
region.
Q105. If a transistor operates at the middle of the
dc load line, a decrease in the
current gain will move the Q point:
(mark1)
Ans:-
A) off the load line
B) nowhere
C) up
D) down