# A cylinder of length L and radius b has its axis coincident with the x-axis. The electric field in this region is….

Q. A cylinder of length L and radius b has its axis coincident with the x-axis. The electric field in this region is $\displaystyle \vec{E}= 200 \hat{i}$ . Find the flux through the left end of the cylinder.

(a) 0

(b) 200 πb²

(c) 100 πb²

(d) 200 πb²

Ans: (d)

Sol: $\displaystyle \phi = \vec{E}.\vec{S}$

Sol: $\displaystyle \phi = (200)\hat{i}.(\pi b^2)(-\hat{i})$