The energy of the EM wave is of the order of 15 KeV. To which part of the spectrum does it belong?
1. X-rays
2. Infrared rays
3. Ultraviolet rays
4. -rays
The electric field associated with an electromagnetic wave in vacuum is given by \(\mathrm{E}=40 \cos \left(k z-6 \times 10^8 t\right)\), where E, z, and t are in volt/m, meter, and second respectively. The value of the wave vector k would be:
1.
2.
3.
4. 3
The ratio of the amplitude of the magnetic field to the amplitude of electric field for an electromagnetic wave propagating in vacuum is equal to
(1) the speed of light in vacuum
(2) reciprocal of speed of light in vacuum
(3) the ratio of magnetic permeability to the electric susceptibility of vacuum
(4) unity
The decreasing order of the wavelength of infrared, microwave, ultraviolet and gamma rays is
(1) gamma rays, ultraviolet, infrared, microwaves
(2) microwaves, gamma rays, infrared, ultraviolet
(3) infrared, microwave, ultraviolet, gamma rays
(4) microwave, infrared, ultraviolet, gamma rays
The electric field of an electromagnetic wave in free space is given by where t and x are in seconds and meters respectively. It can be inferred that:
1. | The wavelength λ is 188.4 m. |
2. | The wave number k is 0.33 rad/m. |
3. | The wave amplitude is 10 V/m. |
4. | The wave is propagating along +x direction |
Which one of the following pairs of statements is correct?
1. (3) and (4)
2. (1) and (2)
3. (2) and (3)
4. (1) and (3)
An EM wave is propagating in a medium with a velocity \(\overrightarrow{{v}}={v} \hat{i}\). The instantaneous oscillating electric field of this EM wave is along the \(+y\) axis. The direction of the oscillating magnetic field of the EM wave will be along:
1. \(-z \text-\)direction
2. \(+z \text-\) direction
3. \(-y \text-\) direction
4. \(+y \text-\) direction
A \(100~\Omega\) resistance and a capacitor of \(100~\Omega\) reactance are connected in series across a \(220~\text{V}\) source. When the capacitor is \(50\%\) charged, the peak value of the displacement current is:
1. \(2.2~\text{A}\)
2. \(11~\text{A}\)
3. \(4.4~\text{A}\)
4. \(11\sqrt{2}~\text{A}\)
Out of the following options which one can be used to produce a propagating electromagnetic wave?
1. | a stationary charge. |
2. | a chargeless particle. |
3. | an accelerating charge. |
4. | a charge moving at constant velocity. |
Light with an energy flux of \(25\times10^4\) Wm–2 falls on a perfectly reflecting surface at normal incidence. If the surface area is \(15\) cm2, the average force exerted on the surface is:
1. \(1.25\times 10^{-6}\) N
2. \(2.50\times 10^{-6}\) N
3. \(1.20\times 10^{-6}\) N
4. \(3.0\times 10^{-6}\) N
The electric and the magnetic fields, associated with an electromagnetic wave, propagating along the positive Z-axis, can be represented by:
1. \(\left [E=E_{0}\hat{k},~B=B_{0}\hat{i} \right ]\)
2. \(\left [E=E_{0}\hat{j},~B=B_{0}\hat{j} \right ]\)
3. \(\left [E=E_{0}\hat{j},~B=B_{0}\hat{k} \right ]\)
4. \(\left [E=E_{0}\hat{i},~B=B_{0}\hat{j} \right ]\)