Barc Sample Paper

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  • Topic: Superheterodyne receiver, Hertz, Alternating current
  • Pages : 7 (1343 words )
  • Download(s) : 148
  • Published : April 21, 2013
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BARC SAMPLE QUESTION PAPER FOR ELECTRONICS If you like my site please support us by sharing website ( to your friends

1. Differential amplifiers are used in

a. instrumentation amplifiers b. voltage followers c. voltage regulators d. buffers 2.

The output voltage Vo of the above circuit is a. -6V b. -5V c. -1.2V d. -0.2V 3. The ideal OP-AMP has the following characteristics.

a) Ri=∞ ,A=∞ ,R0=0 b) Ri=0 ,A=∞ ,R0=0 c) Ri=∞ ,A=∞ ,R0=∞ d) Ri=0 ,A=∞ ,R0=∞


4. . How many op-amps are required to implement this equation

A. 2 B. 3 C. 4 D. 1 5. A very brief, high voltage spike on an ac power line is called as A. A bleeder B. An arc C. A transient D. An avalanche E. A clipped peak 6. You can find the zener diode in

A. The mixer in a superheterodyne receiver B. The PLL in a circuit for detecting FM C. The product detector in a receiver for SSB D. The voltage regulator in a power supply E. The AF oscillator in an AFSK transmitter 7. A network function can be completely specified by:

(A) Real parts of zeros (B)Poles and zeros (C)Real parts of poles (D)Poles, zeros and a scale factor 8. A unit impulse voltage is applied to one port network having two

linear components. If the current through the network is 0 for t0then the network consists of (A) R and L in series (B)R and L in parallel (C)R and C in parallel (D)R and C in series


9. The Q-factor of a parallel resonance circuit consisting of an inductance

of value 1mH, capacitance of value 10-5F and a resistance of 100 ohms is (A) 1 (B)10 (C) π 20 (D) 100 10. In a travelling electromagnetic wave, E and H vector fields are

(A) (B) (C) (D)

perpendicular in space . parallel in space. E is in the direction of wave travel. H is in the direction of wave travel.

11. The lower cut-off frequency of a rectangular waveguide with inside

dimensions (3 × 4.5 cm) operating at 10 GHz is (A) 10 GHz. (B)9 GHz. (C) 10/9GHz. (D) 10/3GHz. 12. The intrinsic impedance of free space is

(A) 75 ohm. (B)73 ohm. (C)120 π ohm. (D)377ohm.
13. Which

one of the following conditions will not gurantee a distortionless transmission line (A)R = 0 = G (B)RC = LG (C) very low frequency range (R>> ω L, G >> ω C) (D) very high frequency range (R

(a) current controlled capacitor (b) voltage controlled capacitor (c) current controlled inductor (d) voltage controlled inductors 15. In a common emitter, unbypassed resister provides

(a)voltage shunt feedback (b)current series feedback (c)negative voltage feedback (d)positive current feedback 16. Introducing a resistor in the emitter of a common amplifier stabilizes

the dc operating point against variations in

a) Only the temperature b) only the β of the transistor c) Both Temperature & β d) None of the above 17. For the circuit shown in Fig.4, the voltage across the last resistor is V.

All resistors are of Ω 1 . The Vs is given by

(A) 13V. (C) 4V.

(B) 8V. (D)1V.

18. The network has a network function Z(s)=s(s+2)/(s+3)(s+4)

(A)not a positive real function. (B)RL network. (C) RC network. (D)LC network. 19. For a series R-C circuit excited by a d-c voltageof 10V, and with time-

constant s, , τ the voltage across C at time τ = t is given by A. 10(1-e-1) v


B. 10(2-e-2) v C. 10-e-1 volts D. 1-e-1
20. A 2 port network using Z parameter representation is said to be

reciprocal if A. Z11 =Z22 B. Z12 =Z21 C. Z12 = - Z21 D. Z11 – 2Z22 =0 21. Consider a transmission line of characteristic impedance 50 ohms and

the line is terminated at one end by +j50 ohms, the VSWR produced in the transmission line will be (A) +1 (C)infinity (B)zero (D)-1

22. In a certain medium E...
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