Q. 94.2( 13 Votes )
(a) When the voltage supply remains connected:
The capacitance of the capacitor will become K times.
Therefore, C’ = kC
Where k = dielectric constant = 6 × 17.7pF = 106.2 pF
The potential difference across the two plates of the capacitor will remain equal to the supply voltage i.e. 100 V
The charge on the capacitor,
q’ = C’V = 160.2 x 10-12 x 100
= 1.602 x 10-8 C
(b) After the voltage supply is disconnected:
As calculated above, the capacitance of the capacitor, C’ = 106.2 pF
The potential difference will decrease on introducing mica sheet by a factor of K,
The charge on the capacitor,
q’ = C’V’ = 106.2 × 10-12 × 16.67
q’ = 1.77 x 10-9 C
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