Q.1

The number of distinct Boolean expressions of 3 variables is

  • 8
  • 256
  • 64
  • 7
Q.2

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

  • 6
  • 4
  • 12
  • 8
Q.3

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

  • 2 > |Z| > 3
Q.4

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.5

What was the first commercial geostationary communication satellite?

  • INTELSAT 1
  • ECHO
  • INSAT-1A
  • SPUTNIK
Q.6

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.7

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

  • 3
  • 4
  • 5
  • It is compiler dependent
Q.8

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.9

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.10

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.11

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.12

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.13

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.14

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.15

. The signal is __________ .

  • periodic for t > 0
  • non-periodic
  • periodic for t < 0
  • depends on t
Q.16

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.17

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

  • 200
  • 2000
  • 20000
  • 200000
Q.18

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.19

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.20

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.21

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.22

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.23

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.24

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.25

A rectangular waveguide of internal dimensions (a = 4 cm and b =is to be operated in TE11 mode. The minimum operating frequency is

  • 6.25 GHz
  • 6.0 GHz
  • 5.0 GHz
  • 3.75 GHz
Q.26

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

  • 10112
  • 11012
  • 11002
  • 01012
Q.27

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.28

Which of the following is not an electromagnetic device?

  • Hall transducer
  • Transformer
  • Speedometer
  • Eddy current damping device
Q.29

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.30

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
Q.31

Which of the following statements is not correct for thermistors?

  • They have negative temperature coefficient of resistance
  • The sensing element is made of sintered ceramics, which are oxides of metals in the form of beads
  • The variation of resistance with temperature is linear
  • The resistance value at ambient temperature may range from 100 Ω to 100 kΩ
Q.32

Which of the following devices has the 'negative resistance' characteristic?

  • Reflex klystron
  • Gunn diode
  • P-N-P transistor
  • Magnetron
Q.33

Consider the following statements regarding an antenna:

  1. It is a transducer
  2. Its performance is essentially frequency sensitive
  3. It is a reciprocal device
  4. With increase in its effective aperture area, width of the radiated beam increases.
Which of the above statements are correct?
  • 1, 2 and 3
  • 1, 2 and 4
  • 2 and 3 only
  • 1 and 4 only
Q.34

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.35

For plane wave propagating in free space or two conductor transmission line, what must be the relationship between the phase velocity vp , the group velocity vg and speed of light c?

  • vp > c > vg
  • vp < c < vg
  • vp = c = vg
  • vp < vg < c
Q.36

For what positive value of K does the polynomial s4 + 8s3 + 24s2 + 32s + K have roots with zero real parts?

  • 10
  • 20
  • 40
  • 80
Q.37

What is the purpose of a start in RSserial communication protocol?

  • To synchronise receiver for receiving every byte
  • To synchronise receiver for receiving a sequence of byte
  • Acts as a parity bit
  • To synchronise receiver for receiving the last byte
Q.38

Time delay produced by an instruction code given below using 2 MHz clock is:
MVI A, FFH
LOOP: DCR A
JNZ Loop

  • 1783 μs
  • 1787 μs
  • 1781 μs
  • 1797 μs
Q.39

The system which is unstable is __________ .

  • h(t) = RCt . e-1 u(t)
    2-755-30-1.png
    2-755-30-2.png
    2-755-30-3.png
Q.40

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

  • zero
  • one
  • two
  • three
Q.41

Which of the following antennas uses a number of varying length parallel elements?

  • Helical antenna
  • Pyramidal Horn
  • Comer reflection antenna
  • Yagi-Uda antenna
Q.42

. The signal is __________ .

  • periodic for t > 0
  • non-periodic
  • periodic for t < 0
  • depends on t
Q.43

Which one of the following compounds is widely used for making ferrites?

  • FeO
  • CuO
  • MgO
  • Fe2O3
Q.44

. The signal is __________ .

  • periodic for t > 0
  • non-periodic
  • periodic for t < 0
  • depends on t
Q.45

The counter shown in figure is built using 4 negative edge triggered toggle FFs. The FFs can be set synchronously when R =The combinational logic required to realize a modulocounter is

  • F= Q4 Q3 Q2 Q1
  • F= Q4 + Q3 + Q2 + Q1
  • F = Q4 + Q3 + Q2 + Q1
  • F = Q4 Q3 Q2 Q1
Q.46

In a material, the Fermi level is located between the centre of the forbidden band and the conduction band. Then what is that material?

  • A p-type semiconductor
  • An n-type semiconductor
  • An intrinsic semiconductor
  • An insulator
Q.47

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.48

Which one of the following logic families can be operated using a supply voltage from 3 V toV?

  • TTL
  • ECL
  • PMOS
  • CMOS
Q.49

An average response rectifier type electronic voltameter has a d.c. voltage ofV applied to it. What is the meter reading?

  • 7.1 V
  • 10 V
  • 11.1 V
  • 22.2 V
Q.50

Which of the following are included in the architecture of a computer?

  1. Addressing modes, CPU
  2. Instruction set, data formats
  3. Secondary memory, operating system
Select the correct answer from the codes given below:
  • 1 and 2
  • 1 and 3
  • 2 and 3
  • 3 only
0 h : 0 m : 1 s