Displacement current is the same as:

1. Conduction current due to the flow of free electrons
2. Conduction current due to the flow of positive ions
3. Conduction current due to the flow of both positive and negative free charge carriers
4. It is not a conduction current but is caused by the time-varying electric field

Subtopic:  Displacement Current |
 56%
Level 3: 35%-60%
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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. \(\frac{q_{0} A \omega}{d} \cos \omega t\)

Subtopic:  Displacement Current |
 74%
Level 2: 60%+
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In electromagnetic wave the phase difference between electric and magnetic field vectors \(\vec E~\text{and}~\vec B\) is:
1. \(0\)
2. \(\frac{\pi}{2}\)
3. \(\pi\)
4. \(\frac{\pi}{4}\)

Subtopic:  Properties of EM Waves |
 66%
Level 2: 60%+
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An electromagnetic wave going through the vacuum is described by E=E0sin(kx-ωt).

Which is the following is/are independent of the wavelength?

1. \(k\) 2. \(k \over \omega\)
3. \(k \omega\) 4. \( \omega\)
Subtopic:  Properties of EM Waves |
 53%
Level 3: 35%-60%
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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. \(1.6\times10^{-7}~\text{Wb/m}^2\)

Subtopic:  Properties of EM Waves |
 76%
Level 2: 60%+
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The energy density of the electromagnetic wave in vacuum is given by the relation:

1. 12.E2ε0+B22μ0 

2. 12ε0E2+12μ0B2

3. E2+B2C

4. 12ε0E2+B22μ0

Subtopic:  Properties of EM Waves |
 80%
Level 1: 80%+
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A lamp radiates power \(P_0\) uniformly in all directions. The amplitude of electric field strength \(E_0\) at a distance \(r\) from it is:
1. \(E_{0} = \dfrac{P_{0}}{2 \pi\varepsilon_{0} cr^{2}}\)
2. \(E_{0} = \sqrt{\dfrac{P_{0}}{2 \pi\varepsilon_{0} cr^{2}}}\)
3. \(E_{0} = \sqrt{\dfrac{P_{0}}{4 \pi\varepsilon_{0} cr^{2}}}\)
4. \(E_{0} = \sqrt{\dfrac{P_{0}}{8 \pi\varepsilon_{0} cr^{2}}}\)

Subtopic:  Properties of EM Waves |
 65%
Level 2: 60%+
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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

Subtopic:  Properties of EM Waves |
 60%
Level 2: 60%+
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Which of the following statements about electromagnetic waves is/are correct:
A. \(X\text-\)rays in a vacuum travel faster than light waves in a vacuum.
B. The energy of a \(X\text-\)ray photon is greater than that of a light photon.
C. Light can be polarised but \(X\text-\)rays cannot.

Choose the correct option from the given ones:

1. \(A\) and \(B\) only
2. B and \(C\) only
3. \(A,B,\) and \(C\) only
4. \(B\) only

Subtopic:  Electromagnetic Spectrum |
Level 3: 35%-60%
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Which of the following is not Maxwell's equation?
(\(\rho\) = volume charge density, \(J\) = current density, \(m\) = pole strength, \(V\) = volume, \(S\) is a closed surface, and \(C\) is closed loop)
1. \(\oint_S \vec{E} \cdot \overrightarrow{d S}=\frac{1}{\varepsilon_0} \int_V \rho d V\)
2. \(\oint_S \vec{B} \cdot \overrightarrow{d S}=\frac{m}{\mu_0}\)
3. \(\oint_S \vec{E} \cdot \overrightarrow{d l}=-\frac{d}{d t} \int_S \vec{B} \cdot \overrightarrow{d S}\)
4. \(\oint_S \vec{H} \cdot \overrightarrow{d S}=\int_C\left(\vec{J}+\frac{d}{d t}\left(\varepsilon_0 \vec{E}\right)\right) \cdot \overrightarrow{d S}\)
Subtopic:  Maxwell's Equations |
Level 3: 35%-60%
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