A point charge `+10 mu C` is at distance of 5cm directly above the center of a square of side 10 cm as shown in Fig. What is the magnitude of the electric flux through the square ? (Hint. Think of the square of the square as one face of a cube with edge 10 cm)

Explanation

In fig, ABCD is a square of side 10cm. The point charge `+10 mu C` is distance of 5cm, directly above the center of ABCD. We can imagine the square ABCD as one of the six faces of a cube of side 10cm. The charge `+q` is at the center of this cube.
According to Gauss's theorem , total electric flux through all the six faces of the cube `= q//in_(0)`
`:.` Electric flux through the square `phi_(E) = (1)/(6) (q)/(in_(0)) (1)/(6) xx (10xx10^(-6))/(8.85xx10^(-12)) = 1.88xx10^(5) C^(-1)`