- ACase (i) contradicts Gauss’s law for electrostatic fields.
- BCase (ii) contradicts Gauss’s law for magnetic fields.
- CCase (i) agrees with $\oint\text{E.dl=0.}$
- DCase (ii) contradict $\oint\text{H.dl}=\text{I}_\text{en}$.
Solution:
Key concept: The electrostatic field lines, do not form a continuous closed path (this follows from the conservative nature of electric field) while the magnetic field lines form the closed paths.
According to the Gauss' law, $\oint\text{E.ds}=\frac{\text{q}}{\in_0}$ for electronstatic field. It does not contradict foe eletrostatic fields as the elecric field lines do not form a continuous closed path.
According to Gauss' law in magnetism.
$\oint\text{B.ds}=0$
Which implies that number of magnetic field lines entering the Gaussian surface is equal to the number of magnetic field lines leaving it. Therefore case (ii) is not possible.
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(a) If both assertion and reason are true and the reason is the correct explanation of the assertion. |
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(b) If both assertion and reason are true but reason is not the correct explanation of the assertion. |
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(c) If assertion is true but reason is false. |
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(d) If the assertion and reason both are false. |
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(a) Na and Al both have the same threshold frequency |
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(b) Maximum kinetic energy for both the metals depend linearly on the frequency |
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(d) Al is a better photo sensitive material than Na |
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(a) |
(b) |
(c) |
(d) |
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(a) 2.28 V |
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(c) 6.28 V |
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(a) Convex mirror |
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(b) Concave mirror |
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(c) Concave lens |
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(d) Two plane mirrors inclined at an angle of 90° |
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(a) |
(b) |
(c) |
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