Question

A cylinder is placed in a uniform electric field e with its axis parallel to the field show that the total electric flux through the cylinder is zero

Answer 1

Electric flux over the curved surface is
given by,
ϕ=∫E.ds cos90°
ϕ=0
Moreover, the flux over the end faces of
the cylinder is zero.
The flux or the lines of forces entering
the cylinder at one end leaves the other
end is same.
ϕ
out
=
EπR
2
−
EπR
2
=0
where, E=electric field
R=radius of cylinder
ϕ
out
=outward flux
Hence, total flux electric flux is zero.

Answer 2

Explanation:

1. electric flux =E.dA
2. cos 90 is 0 so electric flux is zero