MCQ
An electromagnetic wave with frequency $\omega $ and wavelength $\lambda $ travels in the $+y$ direction. Its magnetic field is along $+x$ axis. The vector equation for the associated electric field (of amplitude $E_0$) is
  • A
    $\vec E = {E_{0\,}}\,\cos \left( {\omega t - \frac{{2\pi }}{\lambda }y} \right)\hat x$
  • B
    $\vec E = -{E_{0\,}}\,\cos \left( {\omega t + \frac{{2\pi }}{\lambda }y} \right)\hat x$
  • C
    $\vec E = -{E_{0\,}}\,\cos \left( {\omega t + \frac{{2\pi }}{\lambda }y} \right)\hat z$
  • $\vec E = {E_{0\,}}\,\cos \left( {\omega t - \frac{{2\pi }}{\lambda }y} \right)\hat z$

Answer

Correct option: D.
$\vec E = {E_{0\,}}\,\cos \left( {\omega t - \frac{{2\pi }}{\lambda }y} \right)\hat z$
d
$\vec E = \vec B \times \vec V\,{\rm{(for\, direction)}}$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

Two equal forces ($P$ each) act at a point inclined to each other at an angle of $120^°$. The magnitude of their resultant is
If power factor is $1/2$ in $a$ series $RL$ circuit $R = 100\,\Omega $. $ac$ mains is used then $L$ is
The relationship between pressure and the density of a gas expressed by Boyle’s law, $ P = KD$ holds true
For constructive interference to take place between two monochromatic light waves of wavelength $\lambda$, the path difference should be
The capacitor of capacitance $4\,\mu F$ and $6\,\mu F$ are connected in series. A potential difference of $500\;volts$ is applied to the outer plates of the two capacitor system. The potential difference across the plates of capacitor of $4\,\mu F$ capacitance is.........$volts$
The volume of an air bubble becomes three times as it rises from the bottom of a lake to its surface. Assuming atmospheric pressure to be $75\, cm$ of $Hg$ and the density of water to be $1/10  $ of the density of mercury, the depth of the lake is ....... $m$
A $3\ kg$ sphere dropped through air has a terminal speed of $25\ m/s$. (Assume that the drag force is $-bv$.) Now suppose the sphere is attached to a spring of force constant $k = 300\ N/m$, and that it oscillates with an initial amplitude of $20\ cm$. What is the angular frequencu of its damped $SHM$? ..... $rad/s$
Two liquids of densities $d_1$ and $d_2$ are flowing in identical capillary tubes uder the same pressure difference. Ift $t_1$ and $t_2$ are time taken for the flow of equal quantities (mass) of liquids, then the ratio of coefficient of viscosity of liquids must be
In the circuit shown below, the $ac$ source has voltage $V = 20\cos (\omega t)$ volts with $\omega $=$ 2000 \,rad/sec$. the amplitude of the current will be nearest to......$A$
An observer moves towards a stationary source of sound with a velocity equal to one-fifth of the velocity of sound. The percentage change in the frequency will be $\dots \;$%