2005
NEET
MCQ
AIPMT 2005
In a p-n junction photo cell, the value of the photo-electromotive force profuced by monochromatic light is proportional to
A.
The barrier voltage at the p-n junction.
B.
The intensity of the light falling on the cell.
C.
The frequency of the light falling on the cell.
D.
The voltage applied at the p-n junction.
2005
NEET
MCQ
AIPMT 2005
Choose the only false statement from the following.
A.
In conductors the valence and conduction bands overlap.
B.
Substances with energy gap of the order of 10 eV are insulators.
C.
The resistivity of a semiconductor increases with increase in temperature.
D.
The conductivity of a semiconductor increases with increase in temperature.
2005
NEET
MCQ
AIPMT 2005
Zener diode is used for
A.
amplification
B.
rectification
C.
stabilisation
D.
producing oscillations in an oscillator.
2005
NEET
MCQ
AIPMT 2005
Copper has face centered cubic (fcc) lattice with interatomic spacing equal to 2.54 $\mathop A\limits^ \circ $. The value of lattice constant for this lattice is
A.
2.54 $\mathop A\limits^ \circ $
B.
3.59 $\mathop A\limits^ \circ $
C.
1.27 $\mathop A\limits^ \circ $
D.
5.08 $\mathop A\limits^ \circ $
2005
NEET
MCQ
AIPMT 2005
Application of a forward bias to a p-n junction
A.
widens the depletion zone
B.
increases the potential difference across the depletion zone
C.
increases the number of donors on the n side
D.
decreases the electric field in the depletion zone.
2005
NEET
MCQ
AIPMT 2005
Carbon, silicon and germanium atoms have four valence electrons each. Their valence and conduction bands are separated by energy band gaps represented by (Eg)C, (Eg)si and (Eg)Ge respectively. Which one of the following relationships is true in their case?
A.
(Eg)C > (Eg)Si
B.
(Eg)C < (Eg)Si
C.
(Eg)C = (Eg)Si
D.
(Eg)C < (Eg)Ge.
2004
NEET
MCQ
AIPMT 2004
In semiconductors at a room temperature
A.
the valence band is partially empty and the conduction band is partially filled
B.
the valence band is completely filled and the conduction band is partially filled
C.
the valence band is completely filled
D.
the conduction band is completely empty
2004
NEET
MCQ
AIPMT 2004
The output of OR gate is 1
A.
if both inputs are zero
B.
if either or both inputs are 1
C.
only if both inputs are 1
D.
if either inputs is zero
2004
NEET
MCQ
AIPMT 2004
Of the diodes shown in the following diagrams, which one is reverse biased ?
A.
B.
C.
D.
2004
NEET
MCQ
AIPMT 2004
The peak voltage in the output of a half wave diode rectifier fed with a sinusoidal signal without filter is 10 V. The d.c. component of the output voltage is
A.
(10/$\sqrt 2 $) V
B.
$\left( {{{10} \over \pi }} \right)V$
C.
10 V
D.
(20/$\pi $) V
2003
NEET
MCQ
AIPMT 2003
If a full wave rectifier circuit is operating from 50 Hz mains, the fundamental frequency in the ripple will be
A.
25 Hz
B.
50 Hz
C.
70.7 Hz
D.
100 Hz
2003
NEET
MCQ
AIPMT 2003
A n-p-n transistor conducts when
A.
both collector and emitter are positive with respect to the base
B.
collector is positive and emitter is negative with respect to the base
C.
collector is positive and emitter is at same potential as the base
D.
both collector and emitter are negative with respect to the base
2003
NEET
MCQ
AIPMT 2003
Barrier potential of a p-n junction diode does not depened on
A.
diode design
B.
temperature
C.
forward bias
D.
doping density
2003
NEET
MCQ
AIPMT 2003
Reverse bias applied to a junction diode
A.
lowers the potential barrier
B.
raises the potential barrier
C.
increases the majority carrier current
D.
increases the minority carrier current
2002
NEET
MCQ
AIPMT 2002
The given truth table is for which logic gate
$\matrix{ A & B & Y \cr 1 & 1 & 0 \cr 0 & 1 & 1 \cr 1 & 0 & 1 \cr 0 & 0 & 1 \cr } $
$\matrix{ A & B & Y \cr 1 & 1 & 0 \cr 0 & 1 & 1 \cr 1 & 0 & 1 \cr 0 & 0 & 1 \cr } $
A.
NAND
B.
XOR
C.
NOR
D.
OR.
2002
NEET
MCQ
AIPMT 2002
In a p-n junction
A.
high potential at n side and low potential at p side
B.
high potential at P side and low potential at n side
C.
p and n both are at same potential
D.
undetermined.
2002
NEET
MCQ
AIPMT 2002
For the given circuit of p-n junction diode which is correct
A.
in forward bias the voltage across R is V
B.
in reverse bias the voltage across R is V
C.
in forward bias the voltage across R is 2V
D.
in reverse bias the voltage across R is 2V.
2002
NEET
MCQ
AIPMT 2002
Number of atom per unit cell in B.C.C.
A.
9
B.
4
C.
2
D.
1
2002
NEET
MCQ
AIPMT 2002
For a transistor ${{{I_C}} \over {{I_E}}}$ = 0.96, then current gain for common emitter is
A.
12
B.
6
C.
48
D.
24
2001
NEET
MCQ
AIPMT 2001
The given truth table is for which logic gate
$\matrix{ A & B & Y \cr 1 & 1 & 0 \cr 0 & 1 & 1 \cr 1 & 0 & 1 \cr 0 & 0 & 1 \cr } $
$\matrix{ A & B & Y \cr 1 & 1 & 0 \cr 0 & 1 & 1 \cr 1 & 0 & 1 \cr 0 & 0 & 1 \cr } $
A.
NAND
B.
XOR
C.
NOR
D.
OR
2001
NEET
MCQ
AIPMT 2001
For a common base circuit if ${{{I_C}} \over {{I_E}}}$ = 0.98 then current gain for common emitter circuit will be
A.
49
B.
98
C.
4.9
D.
25.5.
2001
NEET
MCQ
AIPMT 2001
The current in the circuit will be
A.
5/40 A
B.
5/50 A
C.
5/10 A
D.
5/20 A
2000
NEET
MCQ
AIPMT 2000
From the following diode circuit, which diode is in forward biased condition
A.
B.
C.
D.
2000
NEET
MCQ
AIPMT 2000
The cations and anions are arranged in alternate form in
A.
metallic crystal
B.
ionic crystal
C.
covalent crystal
D.
semi-conductor crystal.
2000
NEET
MCQ
AIPMT 2000
The correct relation for $\alpha $, $\beta $ for a transistor
A.
$\beta = {{1 - \alpha } \over \alpha }$
B.
$\beta = {\alpha \over {1 - \alpha }}$
C.
$\alpha = {{\beta - 1} \over \beta }$
D.
$\alpha \beta = 1$