Electromagnetic Field Theory - Section 1 (6)
Electromagnetic Field Theory - Section 1
| 41. | Find the radiation resistance of an antenna of length λ/10 meter? |
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| 42. | A wave is propagated in a waveguide at frequency of 9 GHz and separation is 2 cm between walls find cut off wavelength for dominant mode. |
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| 43. | The input impedance of short-circuited line of length l where λ/4 < l < λ/2, is |
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Answer: Option C Explanation: |
, if Zd comes +j kZC then inductive,
| 44. | A broadside array operating at 100 cm wavelength consist of 4 half-wave dipoles spaced 50 cm apart. Each element carries radio frequency current in the same phase and of magnitude 0.5 A. The radiated power will be |
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Ω.| 45. | The function f(x - vot) represent which of the following? |
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Answer: Option B Explanation: f(x - vot) represents in +ve direction while f(x + vot) represents a progressive wave in -ve direction. |
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| 47. | A broadside array consisting of 200 cm wavelength with 10 half-wave dipole spacing 10 cm. And if each array element feeding with 1 amp. current and operating at same frequency then find the half power beamwidth |
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| 48. | ZL = 200 Ω and it is desired that Zi = 50 Ω The quarter wave transformer should have a characteristic impedance of |
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Answer: Option A Explanation: Z0 = √Zi . ZL |