i)
ii) Battery disconnected after full charge,
Total charge of the system,
=CV+nCV
=(n+1)CV
iii) Inserting dielectric of constant K
Common potential, VC=totalcapacitancetotalcharge
=KC+nC(n+1)CV=K+n(n+1)V
The parallel combination of two air filled parallel plate capacitors of capacitance C and nC is connected to a battery of voltage, V. When the capacitors are fully charged, the battery is removed and after that a dielectric material of dielectric constant K is placed the two plates of the first capacitor. The new potential difference of the combined system is:
Held on 9 Apr 2019 · Verified 6 Jul 2026.
(K+n)(n+1)V
K+nnV
K+nV
V
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