Q.1

Consider the equation s2 + 2s + 2 + K(s +=Where do the roots of this equation break on the root loci plot?

  • -3.414
  • -2.414
  • -1.414
  • -0.414
Q.2

Consider the following statements:

  1. With increase in temperature Fermi-level tries to come in between the energy gap exactly at middle
  2. Mobility of electron in GaAs is very high compared to mobility of hole
  3. In LED, the light energy radiated due to recombination with the aid of traps.
Which of these statements are true?
  • 1 and 2
  • 1, 2 and 3
  • 2 and 3
  • 1 and 3
Q.3

Which of the following output configurations are available in a TTL gate?

  1. Open collector output
  2. Totem pole output
  3. Tristate output
Select the correct answer from the codes given below:
  • 1 only
  • 1 and 2 only
  • 2 and 3 only
  • 1, 2 and 3
Q.4

Which of the following be true for a CE transistor amplifier if the emitter resistor value is made equal to zero?

  1. Its gain will increase
  2. Its stability will increase
  3. Its gain will decrease
  4. Its stability will decrease
Select the correct answer from the codes given below
  • 1 and 2
  • 2 and 3
  • 3 and 4
  • 1 and 4
Q.5

Which of the following equations satisfy Maxwell's equations?

  • Ex = Ey = 0, Ez = cos (y - ct)
    Bx = cos(y - ct), By = Bz = 0
  • Ex = Ey = 0, Ez = cos (y- ct)
    By = cos(y - ct), Bx = Bz = 0
  • Fy = cos (y - ct), Ex = Ez = 0
    Bx = cos(y - ct), By = Bz = 0
  • None of these
Q.6

The characteristic equation of a closed loop system is (s +(s ++ K =The centroid of the asymptotes in root locus is:

  • 2.5
  • -2.5
  • 0.5
  • -0.5
Q.7

For good quality signal transmission all frequency components should have the same transmission delay, td and same phase shift-Φs. What can be said about the statement?

  • Correct
  • True from td but not for Φs
  • Not true for td but true for Φs
  • Both td and Φs are not involved in quality
Q.8

Consider the following statements a half adder.

  1. As a half subtractor also
  2. has two outputs CH = x x y and Sn = x ⊕ y for two inputs x and y
  3. has two outputs CH = x + y and SH = x ⊕ y for two inputs x and y
  4. is a combinational circuit
Which of the statements given above is/are correct?
  • 1, 3, 4
  • 1, 2, 4
  • 4 only
  • 2 and 3
Q.9

Conversion rate, for a successive approximation ADC which uses 2 MHz clock and 5 bit binary ladder containing 8 VV reference voltage is __________ .

  • 64516.12 conversions/sec
  • 400000 conversions/sec
  • 400000 bps
  • 2.5 bps
Q.10

The number of roots of s3 + 2s2 + 7s + 3 = 0 in the left half of the s-plane is :

  • zero
  • one
  • two
  • three
Q.11

The following sequence represents autocorrelation of a real valued signal. The energy of real valued sequence is given by __________ x(n) = {_,_,_,_,_,_,_,_,_}
↑

  • 2[12 + 22 + 32 + 42 + 52 + 62 + 72 + 82 + 92] + 102
  • 10
  • 102
  • 2[12 + 22 + 32 + 42 + 52 + 62 + 72 + 82 + 92 + 102]
Q.12

Consider the following two statements about the internal conditions in an n-channel MOSFET operating in the active region
SThe inversion charge decreases from source to drain
SThe channel potential increases from source to drain
Which of the following is correct?

  • Only S2 is true
  • Both S1 and S2 are false
  • Both S1 and S2 are true, but S2 is not a reason for S1
  • Both S1 and S2 are true, and S2 is a reason for S1
Q.13

  1. Hall coefficient RH is directly proportional to the charge density
  2. RH depends upon type of the semiconductor material (n - type or p - type)
  3. Hall co-efficient RH is directly proportional to hall voltage VH
From the above statements which are the false statements?
  • I only
  • II only
  • III only
  • all of the above
Q.14

In a CMOS CS amplifier, the active load is obtained by connecting a

  • p channel current mirror circuit
  • n channel transistor
  • p channel transistor
  • BJT current mirror
Q.15

The expression given is F(A, B, C, D, E, F, G, H) = Σ(255); then the __________ and __________ minterms are grouped together into dual and variable __________ is reduced using the dual

  • 243, 233, D
  • 222, 158, B
  • 243, 255, A
  • 229, 243, E
Q.16

A losslessΩ transmission line is terminated+ jΩ, then voltage reflection coefficient and current reflection coefficient are

  • 062 ∠82.88, - 0.62 ∠82.88
  • 10.36 ∠11.296, - 10.36 ∠111.296
  • 0.23 ∠49.1, - 0.23 ∠ + 49.1
  • - 10.36 ∠111.296, 10.36 ∠111.296
Q.17

If the open-loop transfer function is a ratio of a numerator polynomial of degree 'm' and a denominator polynomial of degree 'n', then the integer (n - m) represents the number of:

  • breakaway points
  • unstable poles
  • separate root loci
  • asymptotes
Q.18

The electric field of 2.5 x 107 V/m can give 1 eV energy to condition electron, then in a copper block what will be the mean free path of electron?

  • 5 x 10-8 m
  • 4 x 10-7 m
  • 0.4 m
  • 0.5 m
Q.19

The magnitude plot of a composite signal x(t) = e3jt + e4jt is __________ .

  • Half wave rectified sinusoid
  • Full wave rectified sinusoid
  • Exponentially increasing sinusoid
  • Exponentially decreasing sinusoid
Q.20

The equivalent form of the logical expression (ABC + ABC + ABC + ABC + ABC) is:

  • C + (A ⊕ B)
  • (A + B + C)(A + B + C)
  • (A + B + C)(A + B + C)(A + B + C)
  • (A + B + C)(A + B + C)(A + B + C)
Q.21

Choose correct option for a stable system :

  1. Roots of the characteristic equation of the system are real and negative
  2. Area within the impulse response is finite
  • I is true, II is true
  • I is true, II is false
  • I is false, II is true
  • I is false, II is false
Q.22

The number of distinct Boolean expressions of 3 variables is

  • 8
  • 256
  • 64
  • 7
Q.23

(22)4 + (101)3 - (20)5 = (x)4 + (4)x+1 where x >The value of x is

  • 6
  • 4
  • 12
  • 8
Q.24

The ROC of Z-transform of the discrete time sequence x(n) is

  • 2 > |Z| > 3
Q.25

persons are in a room.of them play hockey,of them play football andof them play both hockey and football. Then the number of persons playing neither hockey nor football is:

  • 2
  • 17
  • 13
  • 3
Q.26

What was the first commercial geostationary communication satellite?

  • INTELSAT 1
  • ECHO
  • INSAT-1A
  • SPUTNIK
Q.27

Which of the following has a major role in implementation of functions calls in C?

  • Processor's registers
  • Data segment
  • The heap
  • System stack
Q.28

What can be the maximum dimension of an array in C language program?

  • 3
  • 4
  • 5
  • It is compiler dependent
Q.29

For a second order instrument, the optimum range of ξ (damping ratio), which gives good frequency response over a wide range of frequencies is

  • 0.5 to 0.6
  • 0.6 to 0.7
  • 0.7 to 0.8
  • 0.8 to 1.0
Q.30

A signal with ±V ranged and 1 KHz band width is being digitized using a sample and hold circuit and abit quantizer. The quantization step is :

  • 1 x 10-9 V
  • 5 x 10-9 V
  • 2.5 x 10-9 V
  • 0.5 x 10-9 V
Q.31

In a series operated thyristor configuration, each thyristor should supportV. However, the three thyristors only support voltage ofV,V andV respectively. Hence, the string efficiency in the case is :

  • 98.45%
  • 45.84%
  • 91.67%
  • none of these
Q.32

A uniform plane wave in the free space is normally incident on an infinitely thick dielectric slab (dielectric constant εr = 9). The magnitude of the reflection coefficient is

  • 0
  • 0.3
  • 0.5
  • 0.8
Q.33

For the system with given characteristic equation
s5 + 4s4 + 8s3 + 8s2 + 7s + 4 = 0
The number of roots on left hand side, right hand side and imaginary axis are respectively.

  • 3, 2, 0
  • 4, 0, 1
  • 3, 0, 2
  • 4, 1, 0
Q.34

Find the electric charge required on the earth and moon to balance their gravitational attraction if the charge on the earth is 12.5 times that on the moon.
Mass of moon = 6.7 x 1022 Kg
Mass of earth = 6 x 1024 Kg
Distance between moon and earth =Km
Universal gravitational constant = 6.7 x 10-11 Nm2/Kg2

  • 48.9 TC
  • 4.89 GC
  • 4.89 TC
  • 48.9 GC
Q.35

If each stage has a gain ofdB and noise figure ofdB, then the overall noise figure of a two stage cascade amplifier will be

  • 10
  • 1.09
  • 1.0
  • 10.9
Q.36

. The signal is __________ .

  • periodic for t > 0
  • non-periodic
  • periodic for t < 0
  • depends on t
Q.37

Assertion (A): When all inputs of a NAND-gate are shorted to get a one input, one output gate, it becomes an inverter.

Reason (R): When all inputs of a NAND-gate are at logic 'O' level, the output is at logic 'I' level.

  • Both A and R are individually true and R is the correct explanation of A
  • Both A and R are individually true but R is not the correct explanation of A
  • A is true but R is false
  • A is false but R is true
Q.38

Effective Q of the equivalent electrical circuit of quartz crystal is of the order of

  • 200
  • 2000
  • 20000
  • 200000
Q.39

Two linearly polarized plane waves A and B travelling in free space in the positive x direction meet at a point. Wave A is polarized in the y direction and the wave B is polarized in the z direction. If the two waves are of equal amplitude and are in phase quadrature, the resultant wave will be

  • circularly polarized
  • elliptically polarized
  • linearly polarized
  • vertically polarized
Q.40

A 3 x 8 decoder with two enable inputs is to be used to address 8 blocks of memory. What will be the size of each memory block when addressed from a sixteen bit bus with two MSBs used to enable the decoder?

  • 2 K
  • 4 K
  • 16 K
  • 64 K
Q.41

Assertion (A): The small signal analysis of a transistor amplifier is done to obtain the current gain, voltage gain and the conversion efficiency of an amplifier.

Reason (R): The small signal analysis of a transistor amplifier uses the small signal parameters of the transistor.

  • Both A and R are individually true and R is the correct explanation of A
  • Both A and R are individually true but R is not the correct explanation of A
  • A is true but R is false
  • A is false but R is true
Q.42

Two identical NMOS transistors M1 and M2 are connected as shown below. Vbias is chosen so that both transistors are in saturation. The equivalent gm of the pair is defined to be
at constant Vout
The equivalent gm of the pair is

  • the sum of individual gm's of the transistors
  • the product of individual gm's of the transistors
  • nearly equal to the gm of M1
  • nearly equal to gm / g0 of M2
Q.43

A speech signal, band limited to 4kHz and peak voltage varying between +and -is sampled at the Nyquist rate. Each sample is quantized and represented by 8 bits. If the bits 0 and 1 are transmitted using bipolar pulses, the minimum bandwidth required for distortion free transmission is

  • 64 kHz
  • 32 kHz
  • 8 kHz
  • 4 kHz
Q.44

A series RLC circuit has a resonance frequency of 1 kHz and a quality factor Q =If each of R, L and C is doubled from its original value, the new Q of the circuit is

  • 25
  • 50
  • 100
  • 200
Q.45

When x(n) is real then the Fourier series coefficients are correlated as __________ .

  • a-k = ak*
  • ak = ak*
  • ak+1 = ak*
  • a-k+1 = ak*
Q.46

Using 4-bit numbers (n =if k = 00112, how is k expressed in 2's complement?

  • 10112
  • 11012
  • 11002
  • 01012
Q.47

In a digital voltmeter the oscillator frequency iskHz and the ramp voltage falls from 8 V to 0 V inms. What is the number of pulses counted by the counter?

  • 800
  • 2000
  • 4000
  • 8000
Q.48

Which of the following is not an electromagnetic device?

  • Hall transducer
  • Transformer
  • Speedometer
  • Eddy current damping device
Q.49

A junction FET, can be used as a voltage variable resistor

  • at pinch-off condition
  • beyond pinch-off voltage
  • well below pinch-off condition
  • for any value of VDS
Q.50

A message signal x(t) is amplitude modulated with carrier c(t).
x(t) = 2 sin 600pt
c(t) = 8 cos (2p x 106 t)
such that the modulated signal is
(8 + 2 sin 600pt) [cos 2p x 106 t]
The total side band power is:

  • 2ω
  • 3ω
  • 1ω
  • 0.5ω
0 h : 0 m : 1 s