Learning Materials
Features
Discover
Chapter 17: Problem 25
The frequency from 3 to \(\mathrm{MHz}\) is known as (A) Audio band (B) Medium frequency band (C) Very high frequency band (D) High frequency band
Over 30 million students worldwide already upgrade their learning with 91影视!
All the tools & learning materials you need for study success - in one app.
Get started for free
An electromagnetic wave in vacuum has the electric and magnetic fields \(\vec{E}\) and \(\vec{B}\), which are always perpendicular to each other. The direction of polarizations is given by \(\vec{X}\) and that of wave propagation by \(\vec{k}\) Then \([2012]\) (A) \(\vec{X} \| \vec{E}\) and \(\vec{k} \| \vec{E} \times \vec{B}\) (B) \(\vec{X} \| \vec{B}\) and \(\vec{K} \| \vec{E} \times \vec{B}\) (C) \(\vec{X} \| \vec{E}\) and \(\vec{k} \| \vec{B} \times \vec{E}\) (D) \(\vec{X} \| \vec{B}\) and \(\vec{k} \| \vec{B} \times \vec{E}\)
A radar has power of \(1 \mathrm{~kW}\) and is operating at a frequency of \(10 \mathrm{GHz}\). It is located on a mountain top of height \(500 \mathrm{~m}\). The maximum distance up to which it can detect object located on the surface of the earth (Radius of earth \(=6.4 \times 10^{6} \mathrm{~m}\) ) is (A) \(16 \mathrm{~km}\) (B) \(40 \mathrm{~km}\) (C) \(64 \mathrm{~km}\) (D) \(80 \mathrm{~km}\)
A plane electromagnetic wave of frequency \(40 \mathrm{MHz}\) travels in free space in the \(x\)-direction. At some point and at some instant, the electric field \(\vec{E}\) has its maximum value of \(750 \mathrm{~N} / \mathrm{C}\) in \(y\)-direction. The wavelength of the wave is (A) \(3.5 \mathrm{~m}\) (B) \(5.5 \mathrm{~m}\) (C) \(7.5 \mathrm{~m}\) (D) \(9.5 \mathrm{~m}\)
The Maxwell's four equations are written as (i) \(\oint \vec{E} \cdot \overrightarrow{d s}=\frac{q_{0}}{\varepsilon_{0}}\) (ii) \(\oint \vec{B} \cdot \overrightarrow{d s}=0\) (iii) \(\oint \vec{E} \cdot \overrightarrow{d l}=\frac{d}{d t} \oint \vec{B} \cdot \overrightarrow{d s}\) (iv) \(\oint \vec{B} \cdot \overrightarrow{d s}=\mu_{0} \varepsilon_{0} \frac{d}{d t} \oint \vec{E} \cdot \overrightarrow{d s}\) The equations which have sources of \(\vec{E}\) and \(\vec{B}\) (A) (i), (ii) and (iii) (B) (i) and (ii) (C) (i) and (iii) (D) (i) and (iv)
During the propagation of electromagnetic waves in a medium (A) Both electric and magnetic energy densities are zero. (B) Electric energy density is half of the magnetic energy density. (C) Electric energy density is half of the magnetic energy density. (D) Flectric energy density is equal to the magnetic energy density.
What do you think about this solution?
We value your feedback to improve our textbook solutions.
Explanations 
Textbooks 
Flashcards 
91影视 AI 
Notes 
Study Plans 
Study Sets 
Find a degree 
Magazine