If two linear antennas having lengths in the ratio $2: 3$ are emitting radiation of wavelengths in the ratio $8: 9$, then the ratio of effective powers radiated by them are in the ratio

The power radiated from a linear antenna of length $l$ is proportional to (Given,$\lambda =$ wavelength of the wave):

In an electromagnetic wave,the electric field and magnetising field are $100\,V\,m^{-1}$ and $0.265\,A\,m^{-1}$ respectively. The maximum energy flow is.......$W\,m^{-2}$.

$A$ microwave and an ultrasonic sound wave have the same wavelength. Their frequencies are in the ratio (approximately):

The electric field of a plane electromagnetic wave is given by $\overrightarrow{E} = E_{0} \frac{\hat{i}+\hat{j}}{\sqrt{2}} \cos (kz+\omega t)$. At $t=0$,a positively charged particle is at the point $(x, y, z) = (0, 0, \frac{\pi}{k})$. If its instantaneous velocity at $t=0$ is $v_{0} \hat{k}$,the force acting on it due to the wave is

Due to the tilting of the Earth,which waves finally disappear?