The efficiency of a bulb of power $60 \ W$ is $16 \%$. The peak value of the electric field produced by the electromagnetic radiation from the bulb at a distance of $2 \ m$ from the bulb is $\left(\frac{1}{4 \pi \epsilon_0}=9 \times 10^9 \ Nm^2 C^{-2}\right)$ (in $Vm^{-1}$)

In electromagnetic waves,the average energy density is associated with what?

In an electromagnetic wave,the electric field $\vec{E}$ and the magnetic field $\vec{B}$ oscillate in the region near the source as:

If the magnetic field of a light wave oscillates parallel to the $y-$ 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 are:

$A$ plane electromagnetic wave of frequency $25\; GHz$ is propagating in vacuum along the $z$-direction. At a particular point in space and time,the magnetic field is given by $\overrightarrow{B} = 5 \times 10^{-8} \hat{j}\; T$. The corresponding electric field $\overrightarrow{E}$ is (speed of light $c = 3 \times 10^{8}\; m/s$):

At an instant,a plane electromagnetic wave has its magnetic field in the direction of the vector $\hat{i}-\hat{j}$ and its electric field is in the direction of $\hat{i}+\hat{j}$. The wave is travelling along which direction?