Which of the following phenomenon proves the transverse nature of electromagnetic waves?

1. Polarisation

2. Interference

3. Diffraction

4. Reflection

The impulse imparted by an electromagnetic pulse of energy 1.5 x 10^-2 joule when it falls normally on a perfectly reflecting surface is

1. 4 x 10^-10 kg-m/s

2. 2 x 10^-10 kg-m/s

3.10^-10 kg-m/s

4. 0.5 x 10^-10 kg-m/s

The electric field vector of an electromagnetic wave is given by, \(\vec{E}=E_0 \sin (\omega t-k x) \hat{j}.\) The corresponding expression for magnetic field is:$\stackrel{}{}$
1. \( \vec{B}=B_0 \sin (\omega t+k x) \hat{k} \)
2. \( \vec{B}=B_0 \sin (\omega t-k x) \hat{k} \)
3. \( \vec{B}=-B_0 \sin (\omega t+k x) \hat{k} \)
4. \( \vec{B}=-B_0 \sin (\omega t-k x) \hat{k}\)

Electromagnetic waves are produced by:

Figure shows a parallel plate capacitor being charged by a battery. If X and Y are two closed curves then during charging $\oint \overrightarrow{B}.d\overrightarrow{l}$ is zero along the curve

1. X only

2. Y only

3. Both X & Y

4. Neither X nor Y

Which one of the following rays (or waves) has maximum speed in air?

1. $\beta$-rays

2. Heat radiations

3. Cosmic rays

4. Ultrasonic waves

What is the energy density of electric field at a distance of 5 m from a point source of EM wave, if the electric field strength at that point be 100 V/m ?

(1) 44 x 10^-9 J/m³

(2) 11 x 10^-9 J/m³

(3) 22 x 10^-9 J/m³

(4) 88 x 10^-9 J/m³

Light with an average flux of \(20~\text{W/cm}^2\) falls on a non-reflecting surface at normal incidence having a surface area \(20~\text{cm}^2\). The energy received by the surface during time span of \(1\) minute is:
1. \(12\times 10^{3}~\text{J}\)
2. \(24\times 10^{3}~\text{J}\)
3. \(48\times 10^{3}~\text{J}\)
4. \(10\times 10^{3}~\text{J}\)