A hollow cylindrical box of length 1 m and area of cross -section `25" cm"^(2)` is placed in a three dimensional coordinate system as shown in the figure. The electric field in the region is given by `E=50x hat(i)`, where E is in `"NC"^(-1)` and x is in metre.
Find

charge enclosed by the cylinder.

Explanation

Using Gauss. law,
`ointE*dS=(q)/(epsilon_(0))" "(becauseointE*dS=phi)`
`rArr0.125=(q)/(8.85xx10^(-12))`
`rArr" "q=8.85xx0.125xx10^(-12)=1.1xx10^(-12)C`