The electric field at a distance 2R from the centre
of a charged conducting spherical shell of radius
R is E. The electric field at a distance R/4 from the
centre of the sphere is?
Answers
Answer:
Let the total charge on the sphere be Q
It is nonconducting dielectric sphere. It is uniformly charged.
So, charge density per volume ρ=
4/3πR
3
Q
=
4πR
3
3Q
.....(1)
Electric field at distance 2R due to the sphere
E=
4πε
1
×
(2R)
2
Q
......(2)
For finding the electric field at a distance
2
R
from the center of sphere, we need to take into account the charge enclosed within the sphere of radius
2
R
only. This obtained from Gauss;s law of flux coming out of a closed spherical surface of radius
2
R
Charge enclosed Q
1
=ρ×Volume
=ρ×
3
4
π(
2
R
)
3
=
6
π
ρR
3
=
6
π
×
4πR
3
3Q
×R
3
=
8
Q
E
1
=
4πε
1
×
(R/2)
2
Q
1
=
4π
1
×
8
Q
×
R
2
4
=
4π
1
×
(2R)
2
Q
=2E