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  • Question

  • The input impedance of short-circuited line of length l where ?/4 < l < ?/2, is


  • Options
  • A. resistive
  • B. inductive
  • C. capacitive
  • D. none of the above

  • Correct Answer
  • capacitive 

    Explanation
    l < ?/4, ZL = 0

    The input impedance of short-circuited line of length l where ?/4 < l < ?/2, is resistive inductive , if Zd comes +j kZC then inductive,

    If Zd comes -j kZC then capacitive.

    for 0 ? l ? 1/4, ? ? l ? 3?/4 will be inductive.

    The input impedance of short-circuited line of length l where ?/4 < l < ?/2, is resistive inductive

    Electromagnetic Field Theory problems

    Search Results

    • 1. Characteristic impedance of a transmission line is 50 ?. Input impedance of the open circuited line.
      Zoc = 100 + J150 ?. When transmission line is short circuited, then value of the input impedance will be

    • Options
    • A. 50 ?
    • B. 100 + J150 ?
    • C. 7.69 + J11.54?
    • D. 7.69 - J11.54 ?
      • Discuss
    • 2. Calculate the wave impedance for TM mode in rectangular waveguide for dominant mode at 3 GHz having

    • Options
    • A. (120p) ?
    • B. 377 ?
    • C. 226 ?
    • D. 629 ?
      • Discuss
    • 3. The torque (in mm) acting on a circular current loop of radius 1 mm in the xy plane, connected at the origin and with current 0.1 A, flowing in the sense of increasing in a magnetic field
      is

    • Options
    • A.
    • B.
    • C. 10-12p
    • D. - 10-12p
      • Discuss
    • 4. Which of the following should dominant wave have?

    • Options
    • A. Lowest cut off frequency
    • B. Highest cut off frequency
    • C. No attenuation
    • D. No phase shift
      • Discuss
    • 5. A short circuited stub is shunt connected to a transmission line as shown in the figure is, if z0 = 500 ohms, the admittance y seen at the function of the stub and the transmission line is

    • Options
    • A. (0.01 - j 0.02) mho
    • B. (0.02 - j 0.01) mho
    • C. (0.04 - j 0.02) mho
    • D. (0.02 + j 0) mho
      • Discuss
    • 6. ZL = 200 ? and it is desired that Zi = 50 ? The quarter wave transformer should have a characteristic impedance of

    • Options
    • A. 100 ?
    • B. 40 ?
    • C. 10000 ?
    • D. 4 ?
      • Discuss
    • 7. For F1 layer the maximum ionic density is 2.3 x 104 electrons per cc. The critical frequency for this layer will be

    • Options
    • A. 1.36 MHz
    • B. 13.6 MHz
    • C. 136 MHz
    • D. 1360 MHz
      • Discuss
    • 8. A wave is propagated in a waveguide at frequency of 9 GHz and separation is 2 cm between walls calculate the phase velocity for dominant mode.

    • Options
    • A. 3 x 108 m/sec
    • B. 5 x 108 m/sec
    • C. 1.5 x 108 m/sec
    • D. 9 x 108 m/sec
      • Discuss
    • 9. A plane wave is characterized by the wave is

    • Options
    • A. linearly polarized
    • B. circularly polarized
    • C. elliptically polarized
    • D. unpolarized
      • Discuss
    • 10. Consider a 300 ?, quarter wave long at 1 GHz transmission line as shown in figure. It is connected to a 10 V, 50 ? source at one end is left open circuited at the other end. The magnitude of the voltage at the open circuit end of the line is

    • Options
    • A. 10 V
    • B. 5 V
    • C. 60 V
    • D. 60/7 volt
      • Discuss

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