Question

Flux emerging from curved surface of hemisphere due to charge Q may be

• A. $\frac{Q}{{ϵ}_0}$
• B. $\frac{Q}{2{ϵ}_0}$
• C. $\frac{3Q}{4{ϵ}_0}$
• D. $\frac{Q}{3{ϵ}_0}$

Answer 1

The correct option is D $\frac{Q}{3{ϵ}_0}$

If charged would have been placed inside hemisphere then flux would have been $\frac{Q}{{ϵ}_0}$.
If it have been placed in such a way that half portion of charge is inside hemisphere then flux would have been $\frac{Q}{2{ϵ}_0}$.
But as less than half of the field from charge is passing through curved surface of hemisphere, therefore
${\varphi }_{hemisphere}<\frac{Q}{2{ϵ}_0}$
So, only option that is possible $=\frac{Q}{3{ϵ}_0}$