If a source is transmitting electromagnetic waves of frequency $8.2 \times 10^6 \,Hz$, then the wavelength of the electromagnetic waves transmitted from the source will be (in $\,m$)

The electric field part of an electromagnetic wave in a medium is represented by $E_x=0, E_y=2.5 \frac{N}{C} \cos \left[ (2\pi \times 10^6 \frac{rad}{s})t - (\pi \times 10^{-2} \frac{rad}{m})x \right]$,and $E_z=0$. The wave is

About $5 \%$ of the power of a $100 \; W$ light bulb is converted to visible radiation. What is the average intensity of visible radiation
$(a)$ at a distance of $1 \; m$ from the bulb?
$(b)$ at a distance of $10 \; m$? Assume that the radiation is emitted isotropically and neglect reflection.

If an optical medium possesses a relative permeability of $\frac{10}{\pi}$ and relative permittivity of $\frac{1}{0.0885}$,then the velocity of light is greater in vacuum than that in this medium by . . . . . . times. $\left(\mu_0=4 \pi \times 10^{-7} \ H/m, \varepsilon_0=8.85 \times 10^{-12} \ F/m, c=3 \times 10^8 \ m/s\right)$

Identify the correct statements from the following descriptions of various properties of electromagnetic waves.
$A$. In a plane electromagnetic wave,the electric field and magnetic field must be perpendicular to each other,and the direction of propagation of the wave should be along the electric field or magnetic field.
$B$. The energy in an electromagnetic wave is divided equally between the electric and magnetic fields.
$C$. Both the electric field and magnetic field are parallel to each other and perpendicular to the direction of propagation of the wave.
$D$. The electric field,magnetic field,and direction of propagation of the wave must be mutually perpendicular to each other.
$E$. The ratio of the amplitude of the magnetic field $(B_0)$ to the amplitude of the electric field $(E_0)$ is equal to the speed of light $(c)$.
Choose the most appropriate answer from the options given below:

The electric field associated with an electromagnetic wave propagating in a dielectric medium is given by $\vec{E} = 30(2 \hat{x} + \hat{y}) \sin \left[2 \pi \left(5 \times 10^{14} t - \frac{10^7}{3} z\right)\right] \text{V m}^{-1}$. Which of the following option$(s)$ is(are) correct?
[Given: The speed of light in vacuum,$c = 3 \times 10^8 \text{ m s}^{-1}$]
$(A)$ $B_x = -2 \times 10^{-7} \sin \left[2 \pi \left(5 \times 10^{14} t - \frac{10^7}{3} z\right)\right] \text{Wb m}^{-2}$.
$(B)$ $B_y = 2 \times 10^{-7} \sin \left[2 \pi \left(5 \times 10^{14} t - \frac{10^7}{3} z\right)\right] \text{Wb m}^{-2}$.
$(C)$ The wave is polarized in the $xy$-plane with a polarization angle $\theta = \tan^{-1}(0.5)$ with respect to the $x$-axis.
$(D)$ The refractive index of the medium is $2$.