Q301
Open questionThe magneto-motive force is
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ECE · all questionsElectromagnetic Field Theory
Electromagnetic Field Theory
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Q302
Open questionWhen the phase velocity of an electromagnetic wave depends on frequency in any medium, the phenomenon is called
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Q303
Open questionGauss theorem is expressed mathematically as:
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Q304
Open question"The surface integral of curl of a vector field over an open surface equals the line integral of the vector field over the closed curve bounding the surface area" this is the statement of-
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Q305
Open questionA very reliable service has to be established between two points on earth separated by 1000 km. The band that will be used is
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Q306
Open questionWhat is the magnitude of emf induced in a 200 turn coil with cross-sectional area of 0.16 m2, if the magnetic field through the coil changes from 0.10 Wb/m2 to 0.50 Wb/m2 at a uniform rate over a period of 0.02 seconds?
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Q307
Open questionThe characteristic impedance of a lossless transmission line is given by
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Q308
Open questionConsider the following statements regarding the load matching and impedance measurements:
1. A mismatched load can be properly matched to a line by inserting prior to the load a transmission line long.
2. For matching of 120 Ω load to a 75 Ω line, the quarter-wave transformer must have a characteristic impedance of 190 Ω.
3. The main disadvantage of single-stub matching is that it is a narrow-band or frequency-sensitive device.
Which of the above statements are not correct?
1. A mismatched load can be properly matched to a line by inserting prior to the load a transmission line long.
2. For matching of 120 Ω load to a 75 Ω line, the quarter-wave transformer must have a characteristic impedance of 190 Ω.
3. The main disadvantage of single-stub matching is that it is a narrow-band or frequency-sensitive device.
Which of the above statements are not correct?
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Q309
Open questionWhat is the minimum value of VSWR that may exist on a transmission line?
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Q310
Open questionThe electric field around a positive charge is
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Q311
Open questionThe wavelength of the wave having propagation constant (0.314 + j0.628) per metre is equal to:
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Q312
Open questionMany circles are drawn in a Smith chart used for transmission line calculations. The circles shown in the figure represent
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Q313
Open questionFind the SWR, if the reflection coefficient is 0.8.
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Q314
Open questionA dual directional coupler is connected in a microwave reflectometer measurement setup. The reading of the power meter in the forward direction is 100 mw and in the reverse direction 4 mw. The VSWR is
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Q315
Open questionThe characteristics impedance of quarter wave transformer with load and input impedances given by 30 and 75 respectively is-
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Q316
Open questionIf and the time averaged poynting vector is
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Q317
Open questionFor distortion less transmission through a channel, the channel should be such that
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Q318
Open questionAn electromagnetic wave propagates through a lossless insulator with a velocity 1.5 × 1010 cm/s. Calculate the electric and magnetic properties of the insulator if its intrinsic impedance is 90 π ohms.
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Q319
Open questionFor a lossless transmission line L = 0.35 µH/m. C = 90 pF/m and frequency = 500 MHz. Then the magnitude of propagation constant is:
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Q320
Open questionThe gradient of the function f(x, y) = x + y at the point (0, 0) is
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