Question

An isolated Sherical capacitor having radius 18 cm
find its capacitance and
energy stored if a potential of 100V is applied on it.​

Answer 1

Answer:

Radius of the inner sphere, r

2

= 12 cm = 0.12 m

Radius of the outer sphere, r

1

= 13 cm = 0.13 m

Charge on the inner sphere, q=2.5×10

−6

C

Dielectric constant of a liquid, ε

r

=32

(a)

Capacitance, C=

r

1

−r

2

4πε

o

ε

r

r

1

r

2

where,

ε

o

= Permittivity of free space =8.85×10

−12

C

2

N

−1

m

2

∴C≈5.5×10

−9

F

(b)

Potential of the inner sphere is given by,

V=q/C

=4.5×10

2

V

(c)

Radius of an isolated sphere, r= 12 cm

Capacitance of the sphere is given by the relation,

C

′

=4πε

o

r

=1.33×10

−11

F

The capacitance of the isolated sphere is less in comparison to the concentric spheres. This is because the outer sphere of the concentric spheres is earthed. Hence, the potential difference is less and the capacitance is more than the isolated sphere.

Answer 2

Answer:

=1.33* 10^ -11 F

Explanation:

hope the answer helps