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  • Question
  • 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

  • Correct Answer
  • V-1 

    Explanation
    The ratio of the diffusion coefficient in a semiconductor has the units V-1 em.V-1 V.cm-1 V.s ..

    More questions

    • 1. Two single phase semi-converters are connected in series to form a series converter. The input is v = Vm sin ?t and a1, a2 are the firing angles. If a1 = 0, the dc output voltage is

    • Options
    • A. (1 + cos a2)
    • B. (2 + cos a2)
    • C. (3 + cos a2)
    • D. (4 + cos a2)
    • Discuss
    • 2. Which one is a linear system?

    • Options
    • A. y[n] = x[n] x x[n - 1]
    • B. y[n] = x[n] + x[n - 10]
    • C. y[n] = x2[n]
    • D. (a) and (c)
    • Discuss
    • 3. The analog signal m(t) is given below m(t) = 4 cos 100 pt + 8 sin 200 pt + cos 300 pt, the Nyquist sampling rate will be

    • Options
    • A. 1/100
    • B. 1/200
    • C. 1/300
    • D. 1/600
    • Discuss
    • 4. To cover all inhabited regions of the Earth, the number of geosynchronous communication satellites required

    • Options
    • A. 5
    • B. 3
    • C. 10
    • D. 2
    • Discuss
    • 5. In an n-p-n transistor biased for operation in forward active region

    • Options
    • A. emitter is positive with respect to base
    • B. collector is positive with respect to base
    • C. base is positive with respect to emitter and collector is positive with respect to base
    • D. none of the above
    • Discuss
    • 6. Consider the following applications

      1. Switch
      2. Attenuator
      3. Phase shifter
      4. Oscillator
      In which of the above can a PIN diode be used?

    • Options
    • A. 1 2 3 and 4
    • B. 1 2 and 3 only
    • C. 1 and 2 only
    • D. 2, 3 and 4 only
    • Discuss
    • 7. The frequency of oscillation in a backward wave oscillator can be changed by

    • Options
    • A. varying the voltage which controls beam velocity
    • B. varying the beam current
    • C. both by varying the beam current and by light varying the voltage which controls beam velocity
    • D. changing the rate of thermionic emission
    • Discuss
    • 8. Two networks are cascaded through an ideal buffer. If td1 and td2 are delay times of network, the overall delay time is

    • Options
    • A. td1 + td2
    • B. t2d1 + t2d2
    • C. td1 + td2
    • D.
    • Discuss
    • 9. In paramagnetic materials

    • Options
    • A. permanent magnetic dipoles exist but the interaction between neighbouring dipoles is negligible
    • B. permanent magnetic dipole do not exist
    • C. permanent magnetic dipoles exist and the interaction between neighbouring dipoles is very strong
    • D. permanent magnetic dipole moment may or may not exist
    • Discuss
    • 10. In a microwave coaxial line, the maximum operating frequency is f max and breakdown strength of dielectric is Ed' Then maximum power handling capacity is proportional to

    • Options
    • A.
    • B.
    • C.
    • D.
    • Discuss


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