The electric field of an electromagnetic wave
in free space is given by :
$\overrightarrow{\mathrm{E}}=10 \cos \left({10}^7\mathrm{t}+\mathrm{kx}\right)\hat{\mathrm{j}} \mathrm{V}/\mathrm{m}$, where t and x
are in seconds and metres respectively. It can
be inferred that :-
(a) The wavelength $\mathrm{\lambda }$ is 188.4 m
(b) The wave number k is 0.33 rad/m
(c) The wave amplitude is 10 V/m
(d) The wave is propagating along +x direction
Which one of the following pairs of statements
is correct :-

1. (a) and (b) 

2. (b) and (c)

3. (a) and (c) 

4. (c) and (d)

In an electric circuit, there is a capacitor of reactance \(100~\Omega\) connected across the source of \(220~\text{V}\). The rms value of displacement current will be:
1. \(2.2~\text{A}\)
2. \(0.22~\text{A}\)
3. \(4.2~\text{A}\)
4. \(2.4~\text{A}\)

Displacement current is the same as:

The charge of a parallel plate capacitor is varying as; \(q = q_{0} \sin\omega t\). The magnitude of displacement current through the capacitor is:
(the plate Area = \(A\), separation of plates = \(d\))
1. \(q_{0}\cos \left(\omega t \right)\)
2. \(q_{0} \omega \sin\omega t\)
3. \(q_{0} \omega \cos \omega t\)
4. \(\frac{q_{0} A \omega}{d} \cos \omega t\)

The rate of change of the voltage of a parallel plate capacitor if the instantaneous displacement current of 1 A is established between the two plates of a 1 $\mu$F parallel plate capacitor:

1. ${10}^6 V/s$

2. 10 V/s

3. ${10}^8 V/s$ 

4. ${10}^{-6} V/s$

The relation between electric field E and magnetic field induction B in electromagnetic waves is given by:

(1) $E=\sqrt{\frac{{\mu }_0}{{\epsilon }_0}} B$

(2) E = cB

(3) E = $\frac{B}{c}$

(4) $E=\frac{B}{c^2}$

In a plane EM wave, the electric field oscillates sinusoidally at a frequency of \(2.5\times 10^{10}~\text{Hz}\) and amplitude \(480\) V/m.  The amplitude of the oscillating magnetic field will be:
1. \(1.52\times10^{-8}~\text{Wb/m}^2\)
2. \(1.52\times10^{-7}~\text{Wb/m}^2\)
3. \(1.6\times10^{-6}~\text{Wb/m}^2\)
4. \(1.6\times10^{-7}~\text{Wb/m}^2\)

The intensity of visible radiation at a distance of \(1\) m from a bulb of \(100\) W which converts only \(5\%\) of its power into light, is:
1. \(0.4\) W/m²
2. \(0.5\) W/m²
3. \(0.1\) W/m²
4. \(0.01\) W/m²

On an EM wave, the amplitude of electric and magnetic fields are 100 v/m and 0.265 A/m.  The maximum energy flow is

(1) 26.5 $W/m^2$           (2) 46.7 $W/m^2$

(3) 66.5 $W/m^2$            (4) 86.5 $W/m^2$

The most penetrating radiation out of the following is: 

(1) X-rays        (2) $\beta$-rays            (3) $\alpha$-rays           (4) $\gamma$-rays