Q16 of 37 Page 46

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?

Flux, Φ = q/ε0


Where, q = net charged enclosed


ε0 = permittivity of free space


ε0 = 8.85 × 10-12N-1 m-2C2


Since no charge is enclosed by the cube, i.e. q = 0, the net flux through the Cube is zero.



Note: The number of field lines entering the cube is equal to the number of field lines leaving the cube. Hence the net flux becomes zero.


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