InterviewSolution
Saved Bookmarks
InterviewSolution
| 1. |
A system consits of a uniformly charged sphere of radius R and a surrounding medium filled by a charge with the volume density `rho=alpha/r`, where `alpha` is a positive constant and r is the distance from the centre of the sphere. Find the charge of the sphere for which the electric field intensity E outside the sphere is independent of R.A. `alpha/(2epsilon_(0))`B. `2/(alphaepsilon_(0))`C. `2pialphaR^(2)`D. None of these |
|
Answer» Correct Answer - C Using Gauss theorem for spherical surface of radius r outside the sphere with a uniform charge density `rho` and a charge q `underset(s)intE.ds=(Q_(enc))/(epsi_(0))` `E4pir^(2)=(1)/(epsi_(0))(q+underset(R)overset(r)int(alpha)/(r)(4pir^(2))dr),` `E4pir^(2)=((q-2pialphaR^(2)))/(epsi_(0))+(4pialphar^(2))/(2 epsi_(0))` The intensity E does not depend on R if `(q-2pialphaR^(2))/(epsi_(0))=0or q=2pialphaR^(2)` |
|