The inward and outward electric flux for a closed surface unit of `N-m^(2)//C` are respectively `8xx10^(3)` and `4xx10^(3)`. Then the total charge inside the surface is [where `epsilon_(0)=` permittivity constant]

Options

A. `4 xx 10^(3) C`
B. `- 4 xx 10^(3) C`
C. `((- 4 xx 10^(3)))/(epsilon) C`
D. `- 4 xx 10^(3) epsilon_(0) C`

Answer

D

Explanation

By Gauss.s law `phi= (1)/( epsilon_(0)) (Q_("enclosed")) `
` rArr Q_("enclosed") = phi epsilon_(0) = (- 8 xx 10^(3) + 4 xx 10^(3)) epsilon _(0)`
` = - 4 xx 10^(3) epsilon_(0)` coulomb.