If 10c charge is placed on the surface of a sphere having 9x10''V electric potential at its
surface, what is the radius of the sphere?
Answers
Given :
- Charge placed on the surface of sphere , Q= 10 C
- Electric Potential at its surface
To Find :
The Radius of the sphere
Theory :
• Electric potential due to uniformly charged shell / solid conductor or sphere
, r< R
, r = R
, r > R
Where , R = Radius of the sphere or shell
• Electric potential due to uniformly non- conducted sphere
Solution :
We have to Find thr Raduis of the sphere
We know that
Electric Potential due to uniformly charged sphere :
Now , Put the given values
Therefore, the Raduis of the given sphere is 0.1m
Answer:
Given :
Charge placed on the surface of sphere , Q= 10 C
Electric Potential at its surface\sf=9\times10^{11}V=9×10
11
V
To Find :
The Radius of the sphere
Theory :
• Electric potential due to uniformly charged shell / solid conductor or sphere
\sf\:1)V_{in}=\dfrac{KQ}{R}1)V
in
=
R
KQ
, r< R
\sf\:2)V_{surface}=\dfrac{KQ}{R}2)V
surface
=
R
KQ
, r = R
\sf\:3)V_{out}=\dfrac{KQ}{r}3)V
out
=
r
KQ
, r > R
Where , R = Radius of the sphere or shell
• Electric potential due to uniformly non- conducted sphere
\sf\:1)V_{in}=\dfrac{KQ}{2R^3}(3R^2-r^2)1)V
in
=
2R
3
KQ
(3R
2
−r
2
)
\sf\:2)V_{surface}=\dfrac{KQ}{R}2)V
surface
=
R
KQ
\sf\:3)V_{centre}=\dfrac{3}{2}\times\dfrac{KQ}{r}3)V
centre
=
2
3
×
r
KQ
Solution :
We have to Find thr Raduis of the sphere
We know that
Electric Potential due to uniformly charged sphere :
\sf\blue{V=\dfrac{KQ}{R}}V=
R
KQ
\sf\implies\:R=\dfrac{KQ}{V}⟹R=
V
KQ
Now , Put the given values
\sf\implies\:R=\dfrac{9\times10^{9}\times10}{9\times10^{11}}⟹R=
9×10
11
9×10
9
×10
\sf\implies\:R=\dfrac{9\times10^{10}}{9\times10^{11}}⟹R=
9×10
11
9×10
10
\sf\implies\:R=\dfrac{1}{10}⟹R=
10
1
\sf\implies\:R=0.1m⟹R=0.1m
Therefore, the Raduis of the given sphere is 0.1m
Explanation: