Electric Flux Due to a Charge Configuration Figure shows three point charges, `+2q-q` and `+3q`. Two charges `+2q` and `-q` are enclosed within a surface S. What is the electric flux due to this configuration through the surface S ?

Explanation

Electric flux through the closed surface S is
`phi_(S)=(Sigmaq)/(epsilon_(0))=(+2q-q)/(epsilon_(0))=(q)/(epsilon_(0))rArrphi_(S)=(q)/(epsilon_(0))`
Charge `+3q` is outside the closed surface S, threrfore it would not be taken into consideration in applying Gauss. theorem.