Homework Statement
This is the main question.So I'm stuck at the b part
It says that the shell radius is (3)^1/2 - (3-y^2)^1/2 but i would only say (3-y^2)^1/2.Why do we say otherwise?
Homework EquationsThe Attempt at a Solution
i would say the shell radius is (3-y^2)^1/2 but it's wrong
No.You consider that there is a +q at O.So the one has a charge of +q one would push it away(eh,do you call it like that in English), whereas the one with the charge of -q would pull it towards itself.So both the vectors are the same way.You take the sum of it.