MCQ
Assertion : The electrostatic force between the plates of a charged isolated capacitor decreases when dielectric fills whole space between plates.

Reason : The electric field between the plates of a charged isolated capacitance increases when dielectric fills whole space between plates.

  • A
    If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
  • B
    If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.
  • C
    If Assertion is correct but Reason is incorrect.
  • If Assertion is incorrect and Reason is correct.

Answer

Correct option: D.
If Assertion is incorrect and Reason is correct.
d
For isolated capacitor $Q =$ constant, $F =$ constant.

But $E\, = \,\frac{\sigma }{{K\,{ \in _0}}}$, hence $E$ decreases.

$\therefore $ Assertion is incorrect and Reason is correct.

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