A charge q is placed at the center of a cube of side l. What is the electric flux passing through each face of the cube?

Step 1: Applying Gauss Law for cube
Assuming the cube as a Gaussian surface, the total flux passing through the cube of side l can be given as,
Φ = q/ε₀
Step 2: Flux through each face of the cube
As the charge is placed symmetrically to each face of the cube, thus electric flux passing through each face is equal.
∴ Electric flux passing through each face, Φ' = Φ/6 = q/(6ε₀)