- #1
Buffu
- 849
- 146
While reading the book, Electricity and magnetism, the author says that electric field just outside a spherical shell is ##4\pi \sigma##, on it ##4\pi\sigma r_0^2## ,inside is ##0## and outside is ##Q/R^2##.
My derivations :-
For inside,
##E\Delta S = 4\pi Q = 0## since ##Q = 0##.
For outside,
##E \Delta S = 4 \pi {Q} \iff E \cdot 4 \pi R^2= 4 \pi {Q} ##
For just outside,
##E \cdot (4\pi r_0^2) = 4\pi \sigma (4\pi r_0^2)##.
But I am unable to derive the one for "on it", any suggestions what should I do ?
So far I get,
##E \cdot (\Delta S) = 4\pi (\sigma 4\pi r_0^2)##.
What should be ##\Delta S## ?
Note for future readers :-
The charge is ##4\pi\sigma r_0^2## not the Field. I read it incorrectly.
My derivations :-
For inside,
##E\Delta S = 4\pi Q = 0## since ##Q = 0##.
For outside,
##E \Delta S = 4 \pi {Q} \iff E \cdot 4 \pi R^2= 4 \pi {Q} ##
For just outside,
##E \cdot (4\pi r_0^2) = 4\pi \sigma (4\pi r_0^2)##.
But I am unable to derive the one for "on it", any suggestions what should I do ?
So far I get,
##E \cdot (\Delta S) = 4\pi (\sigma 4\pi r_0^2)##.
What should be ##\Delta S## ?
Note for future readers :-
The charge is ##4\pi\sigma r_0^2## not the Field. I read it incorrectly.
Last edited: