NCERT Solutions for Chapter: Electromagnetic Waves, Exercise 1: MCQ

One requires $11\mathrm{eV}$ of energy to dissociate a carbon monoxide molecule into carbon and oxygen atoms. The minimum frequency of the appropriate electromagnetic radiation to achieve the dissociation lies in

A linearly polarized electromagnetic wave given as $E=E_0\hat{i}\cos \left(kz-\omega t\right)$ is incident normally on a perfectly reflecting infinite wall at $z=a$. Assuming that the material of the wall is optically inactive, the reflected wave will be given as

Light with an energy flux of $20 \mathrm{W}/{\mathrm{cm}}^2$ falls on a non-reflecting surface at normal incidence. If the surface has an area of $30 {\mathrm{cm}}^2$, the total momentum delivered (for complete absorption) during $30$ minutes is

The electric field intensity produced by the radiations coming from $100 \mathrm{W}$ bulb at a $3 \mathrm{m}$ distance is $E$. The electric field intensity produced by the radiations coming from $50 \mathrm{W}$ bulb at the same distance is

If $E$ and $B$ represent electric and magnetic field vectors of the electromagnetic wave, the direction of propagation of electromagnetic wave is along

The ratio of contributions made by the electric field and magnetic field components to the intensity of an $EM$ wave is

An $EM$ wave radiates outwards from a dipole antenna, with $E_0$ as the amplitude of its electric field vector. The electric field $E_0$ which transports significant energy from the source falls off as