If $\vec E$ and $\vec B$ represent the electric and magnetic field vectors of an electromagnetic wave,then the direction of propagation of the electromagnetic wave is in the direction of

For electromagnetic waves,the electric field and the magnetic field are .......

An electromagnetic wave is propagating in vacuum along $-\hat{j}$ direction. The magnetic field of the wave is given by $\vec{B} = (2 \times 10^{-8}) \cos [\pi \times 10^{15}(t + \frac{y}{c})] \hat{k} \text{ T}$. The electric field $\vec{E}$ of this wave is $(c = \text{speed of light})$

The sun delivers $10^{3} \,W m^{-2}$ of electromagnetic flux on the Earth's surface. The total power that is incident on a roof of dimensions $6 \,m \times 30 \,m$ is . . . . . . .

The electric field of an electromagnetic wave in free space is $\overrightarrow{E}=57 \cos \left[7.5 \times 10^6 t-5 \times 10^{-3}(3 x+4 y)\right]\ (4 \hat{i}-3 \hat{j})\ N/C$. The associated magnetic field in Tesla is

$A$ plane electromagnetic wave in a non-magnetic dielectric medium is given by $\vec{E} = \vec{E}_0 \sin(4 \times 10^7 x - 50t)$,where distance is in meters and time is in seconds. The dielectric constant of the medium is: