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1. A unity-feedback control system has the open loop transfer function . If the input system is a unit ramp, the steady state error will be

Options

A : 0

B : 0.5

C : 2

D : infinity

2. A certain 8 bit uniform quantization PCM system can accommodate a signal ranging from - 1 V to + V. The rms value of the signal is V . The signal to quantization noise ratio is:

Options

A : 30 dB

B : 46.91 dB

C : 40 dB

D : 49.92 dB

3. In a semiconductor material. The hole concentration is found to be 2 x 2.5 x 10 15 cm -3 . If mobility of carriers is 0.13 m 2 / v-s . Then find the current density if electric field intensity is 3.62 x 10 -19

Options

A : 7.6237 x 10 -4 A/ cm 2

B : 7.6237 x 10 -5 A/ cm 2

C : 7.6237 x 10 -3 A/ cm 2

D : none of these

4. The analog signal given below is sampled at 1200 samples per second. m(t) = 2 sin 120 p t + 3 sin 240 p t + 4 sin 360 p t + 5 sin 480 p t + 6 sin 600 p t + 7 sin 720 p t . The folding (maximum) frequency is __________ .

Options

A : 300 H z

B : 360 H z

C : 600 H z

D : 480 H z

5. A rectangular waveguide, in dominant TE mode, has dimensions 10 cm x 15 cm . The cut off frequency is

Options

A : 10 GH z

B : 1 GH z

C : 15 GH z

D : 25 GH z

6. A noiseless 3 KH z channel can transmit binary at the rate __________ .

Options

A : 12000 bps

B : 10000 bps

C : 6000 bps

D : 3000 bps

7. Radiation resistance of an antenna is 54 ? and loss resistance is 6 ?. If antenna has power gain of 10, then directivity is:

Options

A : 9

B : 11.11

C : data not sufficient

D : 10

8. Consider a unity feedback control system with open-loop transfer function The steady state error of the system due to a unity step input is :

Options

A : zero

B : K

C : 1/K

D : infinite

9. When phase-lag compensation is used in a system, then gain cross over frequency, bandwidth and undamped frequency are respectively

Options

A : Increased, Increased, Increased

B : Increased, Increased, Decreased

C : Increased, Decreased, Decreased

D : Decreased, Decreased, Decreased

10. What is the propagation constant for air filled wave guide with dimensions a = 1.59" and b = 0.795" at 4.95 GHz?

Options

A : 0.6698

B : 0.7698

C : 0.503

D : 0.6598

1. The equivalent form of the logical expression A B C + A B C + ABC + AB C + A B C is

Options

A : C + (A ? B)

B : ( A + B + C)(A + B + C)

C : (A + B + C)( A + B + C)(A + B + C)

D : (A + B + C)( A + B + C )(A + B + C )

2. An air-filled rectangular waveguide has dimensions 8 cm x 10 cm . The phase velocity of guided wave at frequency of 3 GH z for TE 10 mode is

Options

A : 1.5 x 10 8 m/s

B : 5.5 x 10 8 m/s

C : 3.46 x 10 8 m/s

D : 0.18 x 10 7 m/s

3. If x[n] then the sequence x[n] is

Options

A : non-periodic

B : periodic

C : depends on n

D : none of these

6. In a flash type ADC, employing 15 comparators resolution with 10 volts reference; is expected to be :

Options

A : 0.625 V

B : 0.656 V

C : 0.525 V

D : insufficient data

7. Consider the system with and where p and q are arbitrary real numbers. Which of the following statements about the controllability of the system is true?

Options

A : The system is completely state controllable for any non zero values p and q

B : Only p = 0 and q = 0 result in controllability

C : The system is uncontrollable for all values of p and q

D : We cannot conclude about controllability from the given data

8. In a 4 bit weighted resistor D/A converter, the resistor value corresponding to LSB is 32 k?. The resistor value corresponding to MSB will be

Options

A : 32 K?

B : 16 K?

C : 8 K?

D : 4 K?

9. For a = - 1, find the value of V 2

Options

A : ?

B : 0

C : V 1

D : none of the above

10. The specific gravity of tungsten is 13.8 and its atomic weight is 184.0 Assume that there are two free elements per atom. Then the Fermi level or characteristic energy for the crystal in e V will be

Options

A : 8.95 e V

B : -8.95 e V

C : 7.326 e V

D : -7.326 e V

1. As the temperature increases the mobility of electrons __________ .

Options

A : decreases because the number of carries increases with increased collisions

B : increases because the number of carries decreases with decreased collisions

C : remains same

D : none of the above

3. The ratio of the diffusion coefficient in a semiconductor has the units

Options

A : V -1

B : em.V -1

C : V.cm -1

D : V. s

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