What is the net flux of the uniform electric field of Exercise 1.15 through a cube of side 20 cm oriented so that its faces are parallel to the coordinate planes?
Here, E=3×103i^NC−1 A=20×20=400 cm2 Through a face parallel to x−y plane: A1=4×10−2km2 ∴=E1.A1=(3×103i^).(4×10−2k^)=0 A2=4×10−2km2 ∴ϕ2=E.A2=(3×103i^)(4×10−2i^) =120 Nm2c−1 Through a face parallel to ZX plane: A3 In each plane, there is a set two faces of the cube. Through one face electric flux enters and through the other face, an equal flux leaves. Therefore, net flux through the cube, ϕ=(ϕ1−ϕ1)+(ϕ2−ϕ2)+(ϕ3−ϕ3) =0.
