Suppose that intensity of a laser is $\left(\frac{315}{\pi}\right)\, W / m ^{2} .$ The $rms$ electric field, in units of $V / m$ associated with this source is close to the nearest integer is $\left(\epsilon_{0}=8.86 \times 10^{-12} C ^{2} Nm ^{-2} ; c =3 \times 10^{8} ms ^{-1}\right)$

Which of the following statement is false for the properties of electromagnetic waves ?

Light with an average flux of $20\, W / cm ^{2}$ falls on a non-reflecting surface at normal incidence having surface area $20\, cm ^{2} .$ The energy recelved by the surface during time span of $1$ minute is $............J$

If the magnetic field of a light wave oscillates parallel to $y-$ axis and is given by $B_y = B_m\,sin\,(kz -\omega t)$, the direction of wave travel and the axis along which the electric vector oscillates is

Select the correct statement from the following

The electric field part of an electromagnetic wave in a medium is represented by $E_x = 0\,;$

${E_y} = 2.5\,\frac{N}{C}\,\,\cos \,\left[ {\left( {2\pi \, \times \,{{10}^6}\,\frac{{rad}}{m}} \right)t - \left( {\pi  \times {{10}^{ - 2}}\frac{{rad}}{s}} \right)x} \right];$

$E_z = 0$. The wave is