MCQ
There is an air filled $1\,pF$ parallel plate capacitor. When the plate separation is doubled and the space is filled with wax, the capacitance increases to $2\,pF$. The dielectric constant of wax is
  • A
    $2$
  • $4$
  • C
    $6$
  • D
    $8$

Answer

Correct option: B.
$4$
b
(b) $C = \frac{{{\varepsilon _0}A}}{d} = 1\,pF$ and $C' = \frac{{K{\varepsilon _0}A}}{{2d}} = 2\,pF$   

 $K = 4.$

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