If E and B represent electric and magnetic field vectors of the electromagnetic wave, the direction of propagation of the 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 ${\mathrm{E}}_0$, as the amplitude of its electric field vector. The electric field ${\mathrm{E}}_0$, which transports significant energy from the source falls off as:

An electromagnetic wave travels in a vacuum along the z-direction $\mathrm{E}=({\mathrm{E}}_1\hat{\mathrm{i}}+{\mathrm{E}}_2\hat{\mathrm{j}})\cos (\mathrm{kz}-\mathrm{\omega t})$. Choose the correct options from the following.

(a) The associated magnetic field is given as:$\mathrm{ \; B}=\frac{1}{\mathrm{c}}({\mathrm{E}}_1\hat{\mathrm{j}}-{\mathrm{E}}_2\hat{\mathrm{i}})\cos (\mathrm{kz}-\mathrm{\omega t})$
(b) The associated magnetic field is given as:$\mathrm{ \; B}=\frac{1}{\mathrm{c}}({\mathrm{E}}_1\hat{\mathrm{i}}+{\mathrm{E}}_2\hat{\mathrm{j}})\cos (\mathrm{kz}-\mathrm{\omega t})$
(c) The given electromagnetic field is circularly polarised.
(d) The given electromagnetic wave is plane polarised.

A plane electromagnetic wave propagating along x-direction can have the following pairs of E and B.
(a) E_x, B_y
(b) E_y, B_z
(c) B_x, B_z
(d) E_z, B_y

The E.M wave with the shortest wavelength among the following is:

The magnetic field in a plane electromagnetic wave is given by:

$B_Y = 2\times {10}^{-7} \sin (\pi \times {10}^3 x + 3\pi \times {10}^{11} t) T$

Calculate the wavelength. 

A parallel plate capacitor with circular plates of radius 1 m has a capacitance of 1 nF. At t = 0, it is connected for charging in series with a resistor R = 1 M$\Omega$ across a 2V battery (as shown in the figure). Find the magnetic field at a point P, halfway between the centre and the periphery of the plates, after t = 10^–3 s. (The charge on the capacitor at time t is q (t) = CV[1 – exp (–t/$\tau$)], where the time constant $\tau$ is equal to CR.) 

$$\begin{gathered} 1. 0.74\times {10}^{-13} T \\ 2. 0.67\times {10}^{-13} T \\ 3. 0.74\times {10}^{-12} T \\ 4. 0.67\times {10}^{-12} T \end{gathered}$$

A plane electromagnetic wave of frequency 25 MHz travels in free space along the x-direction. At a particular point in space and time, $$\(\vec{E_{0}}=6.3~ \hat{j}~V/m\). What is \(\vec{B_{0}}\) at this point?

$$\begin{gathered} 1. 2.1\times {10}^{-8} \hat{\mathrm{k}} \mathrm{T} \\ 2. 1.2\times {10}^{-8} \hat{\mathrm{k}} \mathrm{T} \\ 3. 2.1\times {10}^{-8} \hat{\mathrm{J}} \mathrm{T} \\ 4. 1.2\times {10}^{-8} \hat{\mathrm{J}} \mathrm{T} \end{gathered}$$

The magnetic field in a plane electromagnetic wave is given by$\mathrm{B}=\left(2\times {10}^{-7}\right)\mathrm{T} \sin \left(0.5\times {10}^3\mathrm{x}+1.5\times {10}^{11}\mathrm{t}\right)$. The wavelength and frequency of the wave are respectively:

$$\begin{gathered} 1. 2.16 \mathrm{cm}, 24.1 \mathrm{GHz} \\ 2. 0.29 \mathrm{cm}, 13.7 \mathrm{GHz} \\ 3. 3.23 \mathrm{cm}, 20.0 \mathrm{GHz} \\ 4. 1.26 \mathrm{cm}, 23.9 \mathrm{GHz} \end{gathered}$$

The magnetic field in a plane electromagnetic wave is given by$\mathrm{B}=\left(2\times {10}^{-7}\right)\mathrm{T} \sin \left(0.5\times {10}^3\mathrm{x}+1.5\times {10}^{11}\mathrm{t}\right)$. The expression for the electric field is:

$$\begin{gathered} 1. {\mathrm{E}}_{\mathrm{z}}=60 \sin \left(0.5\times {10}^3\mathrm{x}+1.5\times {10}^{11}\mathrm{t}\right) \mathrm{V}/\mathrm{m} \\ 2. {\mathrm{E}}_{\mathrm{z}}=60 \sin \left(1.5\times {10}^3\mathrm{x}+0.5\times {10}^{11}\mathrm{t}\right) \mathrm{V}/\mathrm{m} \\ 3. {\mathrm{E}}_{\mathrm{z}}=55 \sin \left(0.5\times {10}^3\mathrm{x}+1.5\times {10}^{11}\mathrm{t}\right) \mathrm{V}/\mathrm{m} \\ 4. {\mathrm{E}}_{\mathrm{z}}=55 \sin \left(1.5\times {10}^3\mathrm{x}+0.5\times {10}^{11}\mathrm{t}\right) \mathrm{V}/\mathrm{m} \end{gathered}$$

Light with an energy flux of 18 W/cm² falls on a non-reflecting surface at normal incidence. If the surface has an area of 20 cm², what is the average force exerted on the surface during a 30 minute time span?

$$\begin{gathered} 1. 2.1\times {10}^{-6} \mathrm{N} \\ 2. 1.8\times {10}^{-6} \mathrm{N} \\ 3. 1.2\times {10}^{-6} \mathrm{N} \\ 4. 2.1\times {10}^{-5} \mathrm{N} \end{gathered}$$

Assume a bulb of efficiency 2.5% as a point source. The peak values of the electric field and magnetic field produced by the radiation coming from a 100W bulb at a distance of 3m are respectively:

$$\begin{gathered} 1. 2.5 \mathrm{V}/\mathrm{m}, 2.2\times {10}^{-8} \mathrm{T} \\ 2. 3.6 \mathrm{V}/\mathrm{m}, 3.6 \mathrm{T} \\ 3. 4.07 \mathrm{V}/\mathrm{m}, 1.4\times {10}^{-8} \mathrm{T} \\ 4. 4.2 \mathrm{V}/\mathrm{m}, 3.4\times {10}^{-6} \mathrm{T} \end{gathered}$$

For a plane electromagnetic wave propagating in the x-direction, which one of the following combinations gives the correct possible directions for the electric field (E) and magnetic field (B) respectively?

A capacitor of capacitance 'C' is connected across an ac source of voltage V, given by

$\mathrm{V}={\mathrm{V}}_0\mathrm{sin\omega t}$

The displacement current between the plates of the capacitor would then be given by: