Recent questions in Electromagnetics

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A rectangular air-filled waveguide has cross section of $4 \mathrm{~cm} \times 10 \mathrm{~cm}$. The minimum frequency which can propagate in the waveguide is$1.5\; \math...
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A very lossy, $\lambda / 4$ long, $50 \; \Omega$ transmission line is open circuited at the load end. The input impedance measured at the other end of the line is approxi...
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535
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The skin depth at $10\; \mathrm{MHz}$ for a conductor is $1 \; \mathrm{cm}$. The phase velocity of an electromagnetic wave in the conductor at $1,000 \; \mathrm{MHz}$ is ...
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(1) Wave tiltUnder-water propagation(2) Faraday RotationGround wave propagationSpace wave propagationIonospheric propagation
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$\mathrm{A} \frac{\lambda}{2}$ section of a $600 \; \Omega$ transmission line, short circuited at one end and open circuited at the other end, is shown in the figure is $...
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A uniform plane wave is normally incident from air on an infinitely thick magnetic material with relative permeability $100$ and relative permittivity $4$ see the figure ...
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397
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A dipole antenna has a $\sin \theta$ radiation pattern where the angle $\theta$ is measured from the axis of the dipole. The dipole is vertically located above an ideal g...
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371
371 views
The magnitudes of the open-circuit and short-circuit input impedance of a transmission line are $100 \; \Omega$ and $25 \; \Omega$ respectively. The characteristic impeda...
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444 views
A $\text{TEM}$ wave is incident normally upon a perfect conductor. The $\mathrm{E}$ and $\mathrm{H}$ fields at the boundary will be, respectively,minimum and minimummaxim...
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507
507 views
If the diameter of a $\frac{\lambda}{2}$ dipole antenna is increased $\operatorname{from} \frac{\lambda}{100}$ to $\frac{\lambda}{50}$, then itsbandwidth increasesbandwid...
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342
342 views
A uniform plane wave in air impinges at $45^{\circ}$ angle on a lossless dielectric material with dielectric constant $\varepsilon_{r}$. The transmitted wave propagates i...
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316 views
For an $8$ feet $(2.4 \mathrm{~m})$ parabolic dish antenna operating at $4 \; \mathrm{GHz}$, the minimum distance required for far field measurement is closest to$7.5 \ma...
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422
422 views
A rectangular waveguide has dimensions $1 \mathrm{~cm} \times 0.5 \mathrm{~cm}$. Its cut-off frequency is$2 \mathrm{~dB}$$5 \mathrm{~dB}$$8 \mathrm{~dB}$$12 \mathrm{~dB}$
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346
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A rectangular waveguide has dimensions $1 \mathrm{~cm} \times 0.5 \mathrm{~cm}$. Its cut-off frequency is$5 \; \mathrm{GHz}$$10 \; \mathrm{GHz}$$15 \; \mathrm{GHz}$$20 \;...
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334
334 views
Two coaxial cables $1$ and $2$ are filled with different dielectric constants $\varepsilon_{r 1}$ and $\varepsilon_{r 2}$ respectively. The ratio of the wavelengths in th...
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339
339 views
Given $\mathrm{E}=10 e^{-f(4 x-k t)} \bar{y} \; \mathrm{V} / \mathrm{m}$ in free space:Write all the four Maxwell's equations in free space.Find $\nabla \times E$.Find $\...
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392
392 views
The three regions shown in figure are all lossless and non-magnetic. Find. Wave impedance in mediums $2$ and $3$.$d$ such that medium $2$ acts as a quarter wave $(\lambda...
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268
268 views
An electric field on a plane is described by its potential\[\mathrm{V}=20\left(r^{-1}+r^{-2}\right)\]where $r$ is the distance from the source. The field is due toa monop...
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413
413 views
Assuming perfect conductors of a transmission line, pure $\text{TEM}$ propagation is $\text{NOT}$ possible incoaxial cableair-filled cylindrical waveguideparallel twin-wi...
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288
288 views
Indicate which one of the following will $\text{NOT}$ exist in a rectangular resonant cavity.$\mathrm{TE}_{110}$$\mathrm{TE}_{011}$$\mathrm{TM}_{110}$$\mathrm{TM}_{111}$