InterviewSolution
Saved Bookmarks
InterviewSolution
| 1. |
(i) Can two equpotential surfaces intersect each other ? Give reason. (ii) Two charges `+ q and -q` are located at points A `(0, 0, -2) and B(0, 0, 2)` respectively. How much work will be done in moving a test charge from point P`(4, 0, 0) " to " (-5, 0,0)` ? |
|
Answer» (ii) Potential at P (4, 0, 0) is `V_(1) = (-q)/(4 pi epsi_(0)).(1)/(sqrt((4 -0)^(2) + (0 + 2)^(2))) + (q)/(4 pi epsi_(0)).(1)/(sqrt((4 -0)^(2) + (0 -2)^(2)))` `= (-q)/(4 pi epsi_(0)).(1)/(sqrt(16 + 4)) + (q)/(4 pi epsi_(0)) .(1)/(sqrt(16 + 4)) = 0` Potential at `q(-5, 0, 0)` is `V_(2) = (-q)/(4 pi epsi_(0)).(1)/(sqrt((-5 -0)^(2) + (0 + 2)^(2))) + (q)/(4pi epsi_(0)).(1)/(sqrt((-5-0)^(2) + (0-2)^(2)))` `= (-q)/(4pi epsi_(0)).(1)/(sqrt(25 + 4)) + (q)/(4pi epsi_(0)).(1)/(sqrt(25 + 4)) = 0` `:.` Work done `= q (V_(2) - V_(1)) = q (0 -0) = 0` Hence, `w = 0` |
|