2016
Q51
NEET
MCQ
10 Mar 2026
The given circuit has two ideal diodes connected as shown in the figure. The current flowing through the resistance R1 will be
A.
2.5 A
B.
10.0 A
C.
1.43 A
D.
3.13 A
2016
Q52
NEET
MCQ
10 Mar 2026
For CE transistor amplifier, the aufio signal voltage across the collector resistance of 2 k$\Omega $ is 4 V. If the current amplification factor of the transistor is 100 and the base resistance is 1 k$\Omega $, then the input signal voltage is
A.
10 mV
B.
20 mV
C.
30 mV
D.
15 mV
2016
Q53
NEET
MCQ
10 Mar 2026
To get output 1 for the following circuit, the correct choice for the input is
A.
A = 1, B = 1, C = 0
B.
A = 1, B = 0, C = 1
C.
A = 0, B = 1, C = 0
D.
A = 1, B = 0, C = 0
2016
Q54
NEET
MCQ
10 Mar 2026
A npn transistor is connected in common emitter configuration in a given amplifier. A load resistance of 800 $\Omega $ is connected in the collector circuit and the voltage frop across it is 0.8 V. If the current amplification factor is 0.96 and the input resistance of the circuit is 192 $\Omega $, the voltage gain and the power gain of the amplifier will respectively be
A.
4, 4
B.
4, 3.69
C.
4, 3.84
D.
3.69, 3.84
2016
Q55
NEET
MCQ
10 Mar 2026
Consider the junction diode as ideal. The value of current flowing through AB is
A.
10$-$1 A
B.
10$-$3 A
C.
0 A
D.
10$-$2 A
2015
Q56
NEET
MCQ
10 Mar 2026
The input signal given to a CE amplifier having a voltage gain of 150 is Vi = 2cos(15t + ${\pi \over 3}$). The corresponding output signal will be
A.
2cos$\left( {15t + {{5\pi } \over 6}} \right)$
B.
300cos$\left( {15t + {{4\pi } \over 3}} \right)$
C.
300cos$\left( {15t + {{\pi } \over 3}} \right)$
D.
75cos$\left( {15t + {{2\pi } \over 3}} \right)$
2015
Q57
NEET
MCQ
10 Mar 2026
In the given figure, a diode D is connected to an external resistance R = 100 $\Omega $ and an e.m.f. of 3.5 V. If the barrier potential developed across the diode is 0.5 V, the current in the citcuit will be
A.
20 mA
B.
35 mA
C.
30 mA
D.
40 mA
2015
Q58
NEET
MCQ
10 Mar 2026
Which logic gate is represented by the following combination of logic gates ?
A.
AND
B.
NOR
C.
OR
D.
NAND
2015
Q59
NEET
MCQ
10 Mar 2026
If in a p-n junction, a square input signal of 10 V is applied, as shown,
then the output across RL will be
then the output across RL will be
A.
B.
C.
D.
2014
Q60
NEET
MCQ
10 Mar 2026
The barrier potential of a p-n junction depends on
(1) type of semiconductor material
(2) amount of doping
(3) temperature
Which one of the following is correct ?
(1) type of semiconductor material
(2) amount of doping
(3) temperature
Which one of the following is correct ?
A.
(1) and (2) only
B.
(2) only
C.
(2) and (3) only
D.
(1), (2) and (3)
2014
Q61
NEET
MCQ
10 Mar 2026
The given graph represents V-I characteristic for a semiconductor device.
Which of the following statement is correct ?
Which of the following statement is correct ?
A.
It is V-I characteristic for solar cell where, point A represents open circuit voltage and point B short circuit current.
B.
It is for a solar cell and popints A and B represent open circuit voltage and current, respectively.
C.
It is for a photodiode and points A and B represent open circuit voltage and current, respectively.
D.
It is for a LED and points A and B represent open circuit voltage and short circuit current, respectively.
2013
Q62
NEET
MCQ
10 Mar 2026
The output from a NAND gate is divided into two in parallel and fed to another NAND gate. The resulting gate is a
A.
AND gate
B.
NOR gate
C.
OR gate
D.
NOT gate
2013
Q63
NEET
MCQ
10 Mar 2026
One way in which the operation of a n-p-n transistor differs from that of a p-n-p
A.
The emitter junction injects minority carries into the base region of the p-n-p
B.
The emitter injects holes into the base of the p-n-p and electrons into the base region of n-p-n
C.
The emitter injects holes into the base of n-p-n
D.
The emitter junction is reversed biased in n-p-n
2013
Q64
NEET
MCQ
10 Mar 2026
In an unbiased p-n junction, holes diffuse from the p-region to n-region because of
A.
The attraction of free electrons of n-region.
B.
The higher hole concentration in p-region than that in n-region.
C.
The higher concentration of electrons in the n-region than that in the p-region.
D.
The potential difference across the p-n junction.
2013
Q65
NEET
MCQ
10 Mar 2026
In a n-type semiconductor, which of the following statement is true.
A.
Holes are minority carries and pentavalent atoms are dopants.
B.
Holes are majority carries and trivalent atoms are dopants.
C.
Electrons are majority carries and trivalent atoms are dopants.
D.
Electrons are minority carriers and pentavalent atoms are dopants.
2013
Q66
NEET
MCQ
10 Mar 2026
The output (X) of the logic circuit shown ion figure will be
A.
X = A . B
B.
X = $\overline {A + B} $
C.
X = $\overline {\overline A } .\overline {\overline B } $
D.
X = $\overline {A.B} $
2013
Q67
NEET
MCQ
10 Mar 2026
In a common emitter (CE) amplifier having a voltage gain G, the transistor used has transconductance 0.03 mho and current gain 25. If the above transistor is replaced with another one with transconductance 0.02 mho and current gain 20, the voltage gain will be
A.
${1 \over 3}G$
B.
${5 \over 4}G$
C.
${2 \over 3}G$
D.
1.5G
2012
Q68
NEET
MCQ
10 Mar 2026
The input resistance of a silicon transistor is 100 $\Omega $. Base current is changed by 40 $\mu $A which results in a change in collector current by 2 mA. This transistor is used as a common emitter amplifier with a load resistance of 4 k$\Omega $. The voltage gain of the amplifier is
A.
2000
B.
3000
C.
4000
D.
1000
2012
Q69
NEET
MCQ
10 Mar 2026
To get an output Y= 1 in given circuit which of the following input will be correct ?
A.
A $ \to $ 1, B $ \to $ 0, C $ \to $ 0
B.
A $ \to $ 1, B $ \to $ 0, C $ \to $ 1
C.
A $ \to $ 1, B $ \to $ 1, C $ \to $ 0
D.
A $ \to $ 0, B $ \to $ 1, C $ \to $ 0
2012
Q70
NEET
MCQ
10 Mar 2026
C and Si both have same lattice structure; having 4 bonding electrons in each. However, C is insulator where as Si is intrinsic semiconductor. This is because
A.
In case of C the valence band is not completely filled at absolute zero temperature.
B.
In case of C the conduction band is partly filled even at absolute zero temperature.
C.
The four bonding electrons in the case of C lie in the second orbit, whereas in the case of Si they lie in the third.
D.
The four bonding electrons in the case of C lie in the third orbit , whereas for Si they lie in the fourth orbit.
2012
Q71
NEET
MCQ
10 Mar 2026
Transfer characteristics [output voltage (V0) vs input voltage (Vi)] for a base biased transistor in CE configuration is as shown in the figure. For using transistor as a switch, it is used
A.
in region III
B.
both in region (I) and (III)
C.
in region II
D.
in region I
2012
Q72
NEET
MCQ
10 Mar 2026
Two ideal diodes are connected to a battery as shown in the circuit. The current supplied by the battery is
A.
0.75 A
B.
zero
C.
0.25 A
D.
0.5 A
2012
Q73
NEET
MCQ
10 Mar 2026
The figure shows a logic circuit with two inputs A and B and the output C. The voltage wave forms across A, B and C are as given. The logic circuit gate is
A.
OR gate
B.
NOR gate
C.
AND gate
D.
NAND gate
2012
Q74
NEET
MCQ
10 Mar 2026
In a CE transistor amplifier, the audio signal voltage across the collector resistance of 2 k$\Omega $ is 2 V. If the base resistance is 1 k$\Omega $ and the current amplification of the transistor is 100, the input signal voltage is
A.
0.1 V
B.
1.0 V
C.
1 mV
D.
10 mV
2011
Q75
NEET
MCQ
10 Mar 2026
Pure Si at 500 K has equal number of electron (ne) and hole (nh) concentrations of 1.5 $ \times $ 1016 m$-$3. Doping by indium increases nh to 4.5 $ \times $ 1022 m$-$3. The doped semiconductor is of
A.
p-type having electron concentration ne = 5 $ \times $ 109 m$-$3
B.
n-type with electron concentration ne = 5 $ \times $ 1022 m$-$3
C.
p-type with electron concentration ne = 2.5 $ \times $ 1010 m$-$3
D.
n-type with electron concentration ne = 2.5 $ \times $ 1023 m$-$3
2011
Q76
NEET
MCQ
10 Mar 2026
A Zener diode, having breakdown voltage equal to 15 V, is used in a voltage regulator circuit shown in figure. The current through the diode is
A.
5 mA
B.
10 mA
C.
15 mA
D.
20 mA
2011
Q77
NEET
MCQ
10 Mar 2026
In the following figure, the diodes which are forward biased, are
A.
(A), (B) and (D)
B.
(C) only
C.
(C) and (A)
D.
(B) and (D)
2011
Q78
NEET
MCQ
10 Mar 2026
In forward biasing of the p-n junction
A.
the positive terminal of the battery is connected to p-side and the depletion region becomes thick.
B.
the positive terminal of the battery is connected to n-side and the depletion region becomes thin.
C.
the positive terminal of the battery is connected to n-side and the depletion region becomes thick.
D.
the positive terminal of the battery is connected to p-side and the depletion region becomes thin.
2011
Q79
NEET
MCQ
10 Mar 2026
If a small amount of antimony is added to germanium crystal
A.
it becomes a p-type semiconductor
B.
the antimony becomes an acceptor atom
C.
there will be more free electrons than holes in the semiconductor
D.
its resistance is increased
2011
Q80
NEET
MCQ
10 Mar 2026
A transistor is operated in common emitter configuration at VC = 2 V such that a change in the base current from 100 $\mu $A to 300 $\mu $A produces a change in the collector current from 10 mA to 20 mA. The current gain is
A.
50
B.
75
C.
100
D.
25
2011
Q81
NEET
MCQ
10 Mar 2026
Symbolic representation of four logic gates are shown as
Pick out which ones are for AND, NAND and NOT gates, respectively
Pick out which ones are for AND, NAND and NOT gates, respectively
A.
(ii), (iii) and (iv)
B.
(iii), (ii) and (i)
C.
(iii), (ii) and (iv)
D.
(iii), (iv) and (ii)
2010
Q82
NEET
MCQ
10 Mar 2026
The following figure shows a logic gate circuit with two inputs A and B and the output Y. The voltage waveforms of A, B and Y are as given.
The logic gate is
The logic gate is
A.
NOR gate
B.
OR gate
C.
AND gate
D.
NAND gate
2010
Q83
NEET
MCQ
10 Mar 2026
For transistor action
(1) Base, emitter and collector regions should have similar size and doping concentrations.
(2) The base region must be vety thin and lightly doped.
(3) The emitter-base junction is forward biased and base-collector junction is reverse biased.
(4) Both the emitter-base junction as well as the base-collector junction are forward biased.
Which one of the following pairs of statements is correct?
(1) Base, emitter and collector regions should have similar size and doping concentrations.
(2) The base region must be vety thin and lightly doped.
(3) The emitter-base junction is forward biased and base-collector junction is reverse biased.
(4) Both the emitter-base junction as well as the base-collector junction are forward biased.
Which one of the following pairs of statements is correct?
A.
(4) and (1)
B.
(1) and (2)
C.
(2) and (3)
D.
(3) and (4)
2010
Q84
NEET
MCQ
10 Mar 2026
To get an output Y = 1 in given circuit which of the following input will be correct ?
A.
A $ \to $ 1, B $ \to $ 0, C $ \to $ 0
B.
A $ \to $ 1, B $ \to $ 0, C $ \to $ 1
C.
A $ \to $ 1, B $ \to $ 1, C $ \to $ 0
D.
A $ \to $ 0, B $ \to $ 1, C $ \to $ 0
2010
Q85
NEET
MCQ
10 Mar 2026
A common emitter amplifier has a voltage gain of 50, an input impedance of 100 $\Omega $ and an output impedance of 200 $\Omega $. The power gain of the amplifier is
A.
500
B.
1000
C.
1250
D.
50
2010
Q86
NEET
MCQ
10 Mar 2026
Which one of the following statement is false ?
A.
Pure Si doped with trivalent impurities gives a p-type semiconductor.
B.
Majority carries in a n-type semiconductor are holes.
C.
Minority carries in a p-type semiconductor are electrons.
D.
The resistance of intrinisic semiconductor decreases with increase of temperature.
2010
Q87
NEET
MCQ
10 Mar 2026
The device that can act as a complete electronic circuit is
A.
junction diode
B.
integrated circuit
C.
junction transistor
D.
zener diode
2010
Q88
NEET
MCQ
10 Mar 2026
Which one of the following bonds produces a solid that reflects light in the visible region and whose electrical conductivity decreases with temperature and has high melting point ?
A.
metallic bonding
B.
van der Waal's bonding
C.
ionic bonding
D.
covalent bonding
2009
Q89
NEET
MCQ
10 Mar 2026
A transistor is operated in common-emitter configuration at VC = 2V such that a change in the base current from 100 $\mu $A to 200 $\mu $A produces a change in the collector current from 5 mA to 10 mA. The current gain is
A.
100
B.
150
C.
50
D.
75
2009
Q90
NEET
MCQ
10 Mar 2026
A p-n photodiode is fabricated from a semiconductor with a band gap of 2.5 eV. It can detect a signal of wavelength
A.
4000 nm
B.
6000 nm
C.
4000 $\mathop A\limits^ \circ $
D.
6000 $\mathop A\limits^ \circ $
2009
Q91
NEET
MCQ
10 Mar 2026
Sodium has body centred packing. Distance between two nearest atoms is 3.7 $\mathop A\limits^ \circ $. The lattice parameter is
A.
4.3 $\mathop A\limits^ \circ $
B.
3.0 $\mathop A\limits^ \circ $
C.
8.6 $\mathop A\limits^ \circ $
D.
6.8 $\mathop A\limits^ \circ $
2009
Q92
NEET
MCQ
10 Mar 2026
The symbolic representation of four logic gates are given below
The logic symbols for OR, NOT and NAND gates are respectively
The logic symbols for OR, NOT and NAND gates are respectively
A.
(iv), (i), (iii)
B.
(iv), (ii), (i)
C.
(i), (iii), (iv)
D.
(iii), (iv), (ii)
2008
Q93
NEET
MCQ
10 Mar 2026
The voltage gain of an amplifier with 9% negative feedback is 10. The voltage gain without feedback will be
A.
1.25
B.
100
C.
90
D.
10
2008
Q94
NEET
MCQ
10 Mar 2026
A p-n photodiode is made of a material with a band gap of 2.0 eV. The minimum frequency of the radiation that can be absorbed by the material is nearly
A.
1 $ \times $ 1014 Hz
B.
20 $ \times $ 1014 Hz
C.
10 $ \times $ 1014 Hz
D.
5 $ \times $ 1014 Hz
2008
Q95
NEET
MCQ
10 Mar 2026
If the lattice parameter for a crystalline structure is 3.6 $\mathop A\limits^ \circ $, then the atomic radius in fcc crystal is
A.
2.92 $\mathop A\limits^ \circ $
B.
1.27 $\mathop A\limits^ \circ $
C.
1.81 $\mathop A\limits^ \circ $
D.
2.10 $\mathop A\limits^ \circ $
2007
Q96
NEET
MCQ
10 Mar 2026
For a cubic crystal structure which one of the following relations indicating the cell characteristics is correct ?
A.
a $ \ne $ b $ \ne $ c and $\alpha $ = $\beta $ = $\gamma $ = 90o
B.
a = b = c and $\alpha $ $ \ne $ $\beta $ $ \ne $ $\gamma $ = 90o
C.
a = b = c and $\alpha $ = $\beta $ = $\gamma $ = 90o
D.
a $ \ne $ b $ \ne $ c and ;$\alpha $ $ \ne $ $\beta $ $ \ne $ and $\gamma $ = 90o
2007
Q97
NEET
MCQ
10 Mar 2026
In the energy band diagram of a material shown below, the open circles and filled circles denote holes and electrons respectively. The material is
A.
an insulator
B.
a metal
C.
an n-type semiconductor
D.
a p-type semiconductor.
2007
Q98
NEET
MCQ
10 Mar 2026
Which one of the following represents forward bias diode ?
A.
B.
C.
D.
2007
Q99
NEET
MCQ
10 Mar 2026
In the following circuit, the output Y for all possible inputs A and B is expressed by the truth table.
A.
$\matrix{
A & B & Y \cr
0 & 0 & 1 \cr
0 & 1 & 1 \cr
1 & 0 & 1 \cr
1 & 1 & 0 \cr
} $
B.
$\matrix{
A & B & Y \cr
0 & 0 & 1 \cr
0 & 1 & 0 \cr
1 & 0 & 0 \cr
1 & 1 & 0 \cr
} $
C.
$\matrix{
A & B & Y \cr
0 & 0 & 0 \cr
0 & 1 & 1 \cr
1 & 0 & 1 \cr
1 & 1 & 1 \cr
} $
D.
$\matrix{
A & B & Y \cr
0 & 0 & 0 \cr
0 & 1 & 0 \cr
1 & 0 & 0 \cr
1 & 1 & 1 \cr
} $
2006
Q100
NEET
MCQ
10 Mar 2026
The following figure shows a logic gate circuit with two inputs A and B and the output C.
The voltage waveforms of A, B and C are as shown below.
The logic circuit gate is
The voltage waveforms of A, B and C are as shown below.
The logic circuit gate is
A.
OR gate
B.
AND gate
C.
NAND gate
D.
NOR gate