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2. Electric potential and capacitance — Physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 SciencePhysics2. Electric potential and capacitance1 Mark
MCQ
Assertion : In a cavity within a conductor, the electric field is zero.

Reason : Charges in a conductor reside only at its surface

  • ✓
    If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
  • B
    If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
  • C
    If the Assertion is correct but Reason is incorrect.
  • D
    If both the Assertion and Reason are incorrect.
✓

Answer

Correct option: A.
If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
a
Net field inside the conductor is zero because by virtue of induced charges, applied and induced electric fields are equal and opposite thus the net charge resides on surface only. If any cavity is there inside the conductor, electric field will be zero in it.

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