9
MCQ (Multiple Correct Answer)
An electromagnetic wave travelling along $z$-axis is given as $\mathbf{E}=\mathbf{E}_{\mathbf{o}} \cos (k z-\omega t)$. Choose the correct options from the following
A
The associated magnetic field is given as $B=\frac{1}{C} \hat{\mathbf{k}} \times \mathbf{E}=\frac{1}{\omega}(\hat{\mathbf{k}} \times \mathbf{E})$
B
The electromagnetic field can be written in terms of the associated magnetic field as $\mathbf{E}=c(\mathbf{B} \times \hat{\mathbf{k}})$
C
$\hat{\mathbf{k}} \cdot \mathbf{E}=0, \hat{\mathbf{k}} \cdot \mathbf{B}=0$
D
$\hat{\mathbf{k}} \times \mathbf{E}=0, \hat{\mathbf{k}} \times \mathbf{B}=0$
10
MCQ (Multiple Correct Answer)
A plane electromagnetic wave propagating along $x$-direction can have the following pairs of $\mathbf{E}$ and $\mathbf{B}$.
A
$E_x, B_y$
B
$E_y, B_z$
C
$B_{x^{\prime}} E_y$
D
$E_z, B_y$
11
MCQ (Multiple Correct Answer)
A charged particle oscillates about its mean equilibrium position with a frequency of $10^9 \mathrm{~Hz}$. The electromagnetic waves produced
A
will have frequency of $10^9 \mathrm{~Hz}$
B
will have frequency of $2 \times 10^9 \mathrm{~Hz}$
C
will have wavelength of 0.3 m
D
fall in the region of radiowaves
12
MCQ (Multiple Correct Answer)
The source of electromagnetic waves can be a charge
A
moving with a constant velocity
B
moving in a circular orbit
C
at rest
D
falling in an electric field
13
MCQ (Multiple Correct Answer)
An EM wave of intensity I falls on a surface kept in vacuum and exerts radiation pressure $p$ on it. Which of the following are true?
A
Radiation pressure is $\frac{I}{\mathrm{C}}$ if the wave is totally absorbed
B
Radiation pressure is $\frac{I}{\mathrm{C}}$ if the wave is totally reflected
C
Radiation pressure is $\frac{2 I}{\mathrm{c}}$ if the wave is totally reflected
D
Radiation pressure is in the range $\frac{I}{\mathrm{C}}< p<\frac{2 I}{\mathrm{C}}$ for real surfaces