logo

CuriousTab

CuriousTab

Discussion

Home ‣ Electronics and Communication Engineering ‣ Power Electronics See What Others Are Saying!
  • Question

  • A dc chopper V = 500 V feeds an electric fraction dc series motor. The chopping frequency is 400 Hz. The series inductance required to limit the maximum current swing to 10 A is


  • Options
  • A. 20 mH
  • B. about 31 mH
  • C. about 51 mH
  • D. about 92 mH

  • Correct Answer
  • about 31 mH 

    Explanation
    A dc chopper V = 500 V feeds an electric fraction dc series motor. The chopping frequency is 400 Hz..

    More questions

    • 1. In which region of a CE bipolar transistor is collector current almost constant?

    • Options
    • A. Saturation region
    • B. Active region
    • C. Breakdown region
    • D. Both saturation and active region
      • Discuss
    • 2. The Q factor of a waveguide resonator is given by (?0 is resonant frequency, U is energy storage and WL is the power loss)

    • Options
    • A.
    • B.
    • C. Q = ?0UWL
    • D.
      • Discuss
    • 3. In a resistance strain gauge, G = 2, stress = 1050 kg/cm2, R = 1000 ?. The value of ?R will be

    • Options
    • A. 2 ?
    • B. 3 ?
    • C. 4 ?
    • D. 1 ?
      • Discuss
    • 4. In a broadcast superheterodyne receiver

    • Options
    • A. the local oscillator operates below the signal frequency
    • B. local oscillator frequency is normally double the IF
    • C. RF amplifier normally works at kHz above the carrier frequency
    • D. mixer input must be tuned to the signal frequency
      • Discuss
    • 5. FM receivers using the standard 88 to 108 MHz band use IF of

    • Options
    • A. 8 MHz
    • B. 9.9 MHz
    • C. 10.7 MHz
    • D. 12.2 MHz
      • Discuss
    • 6. Which one of the following potential does not satisfy Laplace's equations?

    • Options
    • A. v = 10 xy
    • B. v = p cos ?
    • C.
    • D. v = f cos ? + 10
      • Discuss
    • 7. The rate at which information can be carried through a communication channel depends on

    • Options
    • A. carrier frequency
    • B. bandwidth
    • C. transmission loss
    • D. transmitted power
      • Discuss
    • 8. Generally the wall thickness of rectangular waveguide is

    • Options
    • A. about 1-5 mils
    • B. about 40-100 mils
    • C. about 0.1 to 0.5 mils
    • D. about 500 mils
      • Discuss
    • 9. It is known that noise phase modulates the FM wave. As the noise side band frequency approaches the carrier frequency, the noise amplitude

    • Options
    • A. will increase
    • B. will decrease
    • C. will remain constant
    • D. will reduce to negligible value
      • Discuss
    • 10. Curie Weiss law is .

    • Options
    • A. True
    • B. False
      • Discuss

    Comments

    There are no comments.
Enter a new Comment




Aptitude

Engineering

Programming

Reasoning

Links

Copyright ©CuriousTab. All rights reserved.