KCET 2021 Physics Solved Paper

Energy stored in a capacitor is given as
U=

1

2

CV2 ...(i)
where, C is the capacitance. From the given graph,we get Slope =tan‌θ=

Q

V

=

120µC

10V

...(ii)
As we know, capacitance is given as
C=

Q

V

Substituting the value of

Q

V

from Eq. (ii) in the above relation, we get
C=

120µC

10V

=

120×10−6

10

=12×10−6F
=12µF
Now, substituting the values of C and V in Eq. (i), we get
U=

1

2

×12×(10)2
=600µJ