Explanation:
For a capacitor, we have:
Q = CV
If Q is changing, there will be a current in capacitor plates,
$\text{I}=\frac{\text{dQ}}{\text{dt}}=\frac{\text{CdV}}{\text{dt}}$when voltage across the capacitor is constant, $\frac{\text{dV}}{\text{dt}}=0$
therefore, I = 0
It implies that, for a DC (constant) voltage, the capacitor current is zero.
Hence, for a DC source the conduction current and displacement current (capacitor current) are not same.
Whereas, by Maxwell's equation for a time varying voltage (AC voltage), both conduction and displacement currents are same.
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A non-conducting solid sphere of radius R is uniformly charged. The magnitude of the electric field due to the sphere at a distance r from its centre
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(a) Increases as r increases for r < R |
(b) Decreases as r increases for 0 < r < ∞ |
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(c) Decreases as r increases for R < r < ∞ |
(d) a, c |
The minimum energy required to excite a hydrogen atom from its ground state is
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(a) 13.6 eV |
(b) -13.6 eV |
(c) 3.4 eV |
(d) 10.2 eV |
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(a) 3 min 20 sec |
(b) 5 min |
(c) 7 min 30 sec |
(d) 2 min 30 sec |
At the time of total solar eclipse, the spectrum of solar radiation would be
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(a) A large number of dark Fraunhofer lines |
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(b) A less number of dark Fraunhofer lines |
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(c) No lines at all |
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(d) All Fraunhofer lines changed into brilliant colours |
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(a) Clockwise of the +ve z axis |
(b) Anticlockwise of the +ve z axis |
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(c) Zero |
(d) Along the magnetic field |
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(a) Half |
(b) Double |
(c) One fourth |
(d) Unchanged |