Source of an electromagnetic wave is

(1) A charge moving with constant velocity

(2) A charge at rest

(3) A charge moving in a circular orbit

(4) Charges cannot produce an EM wave

The dimension of E/H is that of 

(1) Impedance

(2) Inductance

(3) capacitance

(4) Inductance$\times$Capacitance

Poynting vector $\overrightarrow{P}$ for an EM wave is :

1. $\overrightarrow{P}=\overrightarrow{E}\times \overrightarrow{B}$

2. $\overrightarrow{P}=\overrightarrow{E}\times \overrightarrow{H}$

3. $\overrightarrow{P}=\frac{\overrightarrow{E}}{\overrightarrow{B}}$

4. $\overrightarrow{P}=\frac{\overrightarrow{E}}{\overrightarrow{H}}$

Which one statement is incorrect about the electromagnetic waves?

(1) $\overrightarrow{E}\times \overrightarrow{B}$ gives always the direction of propagation

(2) $\overrightarrow{E}$ is always perpendicular to $\overrightarrow{B}$

(3) Transverse in nature

(4) $\overrightarrow{E}$ is always parallel to $\overrightarrow{B}$

Instantaneous displacement current of \(2.0\) A is set up in the space between two parallel plates of \(1~\mu \text{F}\)$$ capacitor. The rate of change in potential difference across the capacitor is:
1. \(3\times 10^{6}~\text{V/s}\)
2. \(4\times 10^{6}~\text{V/s}\)
3. \(2\times 10^{6}~\text{V/s}\)
4. None of these

Which statement is incorrect?

Displacement current is:

A radiowave has a maximum magnetic field induction of ${10}^{-4}$ T on arrival at a receiving antenna. The maximum electric field intensity of such a wave is

(1) zero

(2) $3\times {10}^4 V/m$

(3) $5.8\times {10}^{-9} V/m$

(4) $3.3\times {10}^{13 } V/m$

The shortest wavelength is for 

(1) $\gamma$-rays

(2) X-rays

(3) ultraviolet rays

(4) microwaves