Question

A capacitor stores 10C charge when connected across a
battery. When the gap between the plates is filled with a
dielectric, a charge of 20uC flows through the battery. Find
the dielectric constant of the dielectric.​

Answer 1

Explanation:

The capacitance before filled with dielectric is C=

d

Aϵ

0

The capacitance after filled with dielectric is C

′

=

d

Akϵ

0

=kC

Initial charge, Q=60μC and total charge after filled with dielectric Q

′

=120+60=180μC

Here, Q=CV and Q

′

=C

′

V=kCV

Q

Q

′

=

CV

kCV

k=

Q

Q

′

=

60

180

=3