Five charges q1,q2,q3,q4 and q5 are fixed at their positions as shown in Figure. S is a Gaussian surface. The Gauss’s law given by which of the following statements is correct?
∮→E.→ds=qε0
As we know, Electric field is due to all the charges present inside as well as outside the closed surface, while electric flux is due to the charges present inside the gaussian surface only.
Therefore, in left side equation, the electric field is due to all the charges present both inside as well as outside the Gaussian surface.
This shows E on LHS of the above equation will have a contribution from all charges whereas q on the RHS will have a contribution from q2 and q4 only. Hence option (b) is correct.
Final Answer: (b)