logo

CuriousTab

CuriousTab

Discussion

Home ‣ Electronics and Communication Engineering ‣ Electronic Devices and Circuits See What Others Are Saying!
  • Question

  • At room temperature the current in an intrinsic semiconductor is due to


  • Options
  • A. holes
  • B. electrons
  • C. ions
  • D. holes and electrons

  • Correct Answer
  • holes and electrons 

    Explanation
    Intrinsic material has equal number of holes and electrons.

    More questions

    • 1. If t is relaxation time and tc is average time between collisions, then in an isotropic metal

    • Options
    • A. t = tc
    • B. t < tc
    • C. tc < t
    • D. T = 0.01 te
      • Discuss
    • 2. The selectivity curve of a standard receiver is represented by

    • Options
    • A. curve A
    • B. curve B
    • C. curve C
    • D. curve D
      • Discuss
    • 3. In the given figure shows a 10dB directional coupler. If power input at port 1 is 100 mW, power output at port 3 is

    • Options
    • A. 10 mW
    • B. 15 mW
    • C. 20 mW
    • D. 25 mW
      • Discuss
    • 4. Match the following:

      List I List II
      A. Ring modulator 1. Clock recovery
      B. VCO 2. Demodulation of FM
      C. Foster Seeley discriminator 3. Frequency conversion
      D. Mixer 4. Summing of two points
      5. Generation of FM
      6. Generation of DSB-SC


    • Options
    • A. A-1, B-3, C-2, D-4
    • B. A-6, B-5, C-2, D-3
    • C. A-6, B-1, C-3, D-2
    • D. A-5, B-6, C-1, D-3
      • Discuss
    • 5. A line is excited by a 100 V dc source. If reflection coefficients at both ends are 1 each then

    • Options
    • A. there will be no oscillations on line
    • B. there will be only 1 or 2 oscillations on line
    • C. there will be a finite number of oscillations on line
    • D. the oscillations will continue indefinitely
      • Discuss
    • 6. If a and b are the width and height of rectangular wave-guide the cut off wavelength ?c for TE20 mode is equal to

    • Options
    • A. a
    • B. a + b
    • C. a - b
    • D. a2 + b2
      • Discuss
    • 7. A LASCR has

    • Options
    • A. 4 semiconductor layers and 3 junctions
    • B. 3 semiconductor layers and 2 junctions
    • C. 2 semiconductor layers and 2 junctions
    • D. any of these depending on the rating
      • Discuss
    • 8. A 20 m antenna gives a certain uplink gain at frequencies of 4/6 GHz. For getting same gain in the 20/30 GHz band, antenna size required is metre.

    • Options
    • A. 100
    • B. 4
    • C. 1
    • D. 10
      • Discuss
    • 9. The apparent capacitance at a high angular frequency ? of an air cored capacitor having capacitance C and inductance L is given by

    • Options
    • A.
    • B.
    • C.
    • D.
      • Discuss
    • 10. Decimal number 10 is equal to binary number

    • Options
    • A. 1110
    • B. 1010
    • C. 1001
    • D. 1000
      • Discuss

    Comments

    There are no comments.
Enter a new Comment




Aptitude

Engineering

Programming

Reasoning

Links

Copyright ©CuriousTab. All rights reserved.