Test Papers on Diploma Electrical Engineering

1. The reason of preferring FETs to bipolar transistors in integrated circuits is that
(a) they occupy very small space
(b) it has become a tradition
(c) fabrication of circuit is easy
(d) it is cheaper

2. Out of the following devices, the fastest switching device is
(a) JFET
(b) BJT
(c) MOSFET
(d) Triode

3. When used in circuit, the Zener diode is always
(a) forward-biased
(b) connected in series
(c) troubled by overheating
(d) reverse-biased

4. RC coupling is popular in low-level audio amplifiers because it
(a) has better low frequency response
(b) is inexpensive and needs no adjustments
(c) provides an output signal in phase with the input signal
(d) needs low voltage battery for collector supply

5. The main reason for the variation of amplifier gain with frequency is
(a) the presence of capacitances, both external and internal
(b) due to inter-stage transformers
(c) the logarithmic increase in its output power
(d) the Miller effect

6. An AND gate
(a) implements logic addition
(b) is equivalent to a series switching circuit
(c) is an any-or-all gate
(d) is equivalent to a parallel switching circuit

7. A unique advantageous feature of CMOS family is its
(a) use of NMOS circuits
(b) power dissipation in nanowatt range
(c) speed
(d) dependence on frequency for power dissipation

8. The number of flip-flops required in a decade counter is
(a) 2
(b) 3
(c) 4
(d) 10

9. PROM is
(a) permanent read only memory
(b) polarized read only memory
(c) positive read only memory
(d) programmable read only memory

10. In a microprocessor, the address of the next instruction to be executed, is stored in
(a) stack pointer
(b) address latch
(c) program counter
(d) general purpose register

11. In a microprocessor, the bus which is used to transfer data from main memory to peripheral device is
(a) data bus
(b) input bus
(c) DMA bus
(d) output bus

12. In a microprocessor, an instruction register is storage for
(a) location of data in memory
(b) location of instruction in memory
(c) address of the next instruction to be executed
(d) binary code for the instruction to be executed

13. A modulator is a system to
(a) separate two frequencies
(b) impress the information on to a radio frequency carrier
(c) extract information from the carrier
(d) amplify the audio frequency signal

14. The AM broadcast band is given by
(a) 10 KHz to 30 KHz
(b) 500 KHz to1500 KHz
(c) 3 KHz to 30 MHz
(d) 30 MHz to 300 MHz

15. The most useful modulation technique for high fidelity audio broadcasting on radio in current practice is
(a) amplitude modulation
(b) frequency modulation
(c) pulse amplitude modulation
(d) pulse code modulation

16. The FM radio frequency range is approximately
(a) 250-300 MHz
(b) 150-200 MHz
(c) 90-105 MHz
(d) 30-70 MHz

17. In FM, the noise can be further decreased by
(a) decreasing deviation
(b) increasing deviation
(c) keeping the deviation constant
(d) none of these

18. The effect of noise in a communication system is most adverse with reference to
(a) Source
(b) Channel
(c) Encoder
(d) receiver

19. The demodulation of the sound signals in a TV receiver is accomplished by
(a) linear detector
(b) product detector
(c) discriminator
(d) envelope detector

20. An SCR is also called a
(a) Triac
(b) Thyristor
(c) Diac
(d) unijunction transistor

21. A power chopper converts
(a) A.C to D.C.
(b) D.C. to D.C.
(c) D.C. to A.C.
(d) A.C. to A.C.

22. In FM modulation ,when the modulation index increases, transmitted power is
(a) Constant
(b) Increased
(c) Decreased
(d) none of these

23. In a fully controlled converter the load voltage is controlled by which of the following quantity.
(a) Extension angle
(b) Firing angle
(c) Conduction angle
(d) None of these

24. Reverse saturation current in a transistor
(a) Decreases with increase in temperature
(b) Increases with increase in temperature
(c) Remains same with increase in temperature
(d) None of these

25. A transistor can be used as an amplifier in its
(a) Saturation region
(b) Active region
(c) Both saturation and active region
(d) Cut-off region

More Question Set on Electrical Engineering Diploma MCQs from Various Exam

26. If the peak value of the input voltage to a half wave rectifier is 28.28 volts and no filter is used the maximum dc voltage across the load will be
(a) 20.2V
(b) 15 V
(c) 9 V
(d) 14.14 V

27. It is required to construct a counter to count up to 100(decimal). The minimum number of flip flops required to construct the counter is
(a) 8
(b) 7
(c) 6
(d) 5

28. Which of the following Boolean rules is correct?
(a) A + 0 = 0
(b) A + 1 = 1
(c) A + A = A.A
(d) A + AB = A + B

29. The bit sequence 0010 is serially entered (right-most bit first) into a 4-bit parallel out shift register that is initially clear. What are the Q outputs after two clock pulses?
(a) 0000
(b) 0010
(c) 1000
(d) 1111

30. Which interrupt has the highest priority?
(a) INTR
(b) TRAP
(c) RST6.5
(d) RST7.5

31. A microprocessor with 12 address line is capable of addressing
(a) 1024 locations
(b) 2028 locations
(c) 4096 locations
(d) 64K locations

32. A carrier is simultaneously modulated by two sine waves with modulation indices of 0.4 and 0.3. The resultant modulation index will be
(a) 1.0
(b) 0.7
(c) 0.5
(d) 0.35

33. Carrier signal has
(a) constant magnitude
(b) constant frequency
(c) variable frequency
(d) variable time

34. Turn-off times of a thyristor
(a) depends upon stored charge in the junction.
(b) is a constant.
(c) depends on load.
(d) none of these

35. A zener diode
(a) Has a high forward voltage rating
(b) Has a sharp breakdown at low reverse voltage
(c) Is useful as an amplifier
(d) Has a negative resistance

36. Which one of the following specifications is not correct for a common collector amplifier?
(a) High input impedance
(b) Low output impedance
(c) High voltage gain
(d) High current gain

37. The POS form of expression is suitable for circuit using
(a) XOR
(b) NAND
(c) AND
(d) NOR

38. The program counter in a 8085 microprocessor is a 16-bit register, because
(a) It counts 16 bits at a time
(b) There are 16 address lines
(c) It facilities the user storing 16 bit data temporarily
(d) It has to fetch two 8-bit data at a time

39. Output of the assembler in machine code is referred to as
(a) Object program
(b) Source program
(c) Macroinstruction
(d) Symbolic instruction

40. Both the ALU and control section of CPU employ which special purpose storage locations?
(a) Buffers
(b) Decoders
(c) Accumulators
(d) Registers

41. Eight memory chips of 32×4 bit size have their address buses connected together. What is the size of this memory system?
(a) 512×2 bits
(b) 256×4 bits
(c) 64×16 bits
(d) 32×32 bits

42. In AM, the carrier is changed by a modulating signal. What parameter of the carrier is changed?
(a) amplitude
(b) frequency
(c) pulse width
(d) phase

43. In amplitude modulation, frequency is
(a) Zero
(b) Constant
(c) One
(d) variable

44. In AM modulation when the modulation index increases, transmitted power is
(a) Constant
(b) Increased
(c) decreased
(d) none of these

45. Out of the following semiconductor power devices, which one is not a current triggered device?
(a) Thyristor
(b) GTO
(c) TRIAC
(d) MOSFET

46. With gate open, if the supply voltage exceeds the break over voltage of SCR, then SCR will conduct
(a) False
(b) True
(c) for dc only
(d) for ac only

47. What is the value of total electric flux coming out of a closed surface?
(a) Zero
(b) Equal to volume charge density
(c) Equal to the total charge enclosed by the surface
(d) Equal to the surface charge density

48. In the left hand rule, forefinger always represents
(a) Voltage
(b) Current
(c) Direction of force on the conductor
(d) Magnetic field

49. The transmission line whose characteristic impedance is a purely resistive
(a) Must be a lossless line
(b) Must be a distortionless line
(c) May not be a lossless line
(d) May not be a distortionless line

50. A Yagi antenna has a driven antenna
(a) Only
(b) With a reflector
(c) With one or more directors
(d) With a reflector and one or more directors