Question

A point charge +Q is placed just outside an imaginary hemispherical surface of radius R as shown in the figure. Which of the following statements is/are correct?

(A) The electric flux passing through the curved surface of the hemisphere is \(-\frac{Q}{2ε_0}(1-\frac{1}{\sqrt{2}})\)

(B) Total flux through the curved and the flat surfaces is \(\frac{Q}{ε _ 0}\)

(C) The component of the electric field normal to the flat surface is constant over the surface

(D) The circumference of the flat surface is an equipotential

Answer 1

 (A) The electric flux passing through the curved surface of the hemisphere is \(-\frac{Q}{2ε_0}(1-\frac{1}{\sqrt{2}})\)

(D) The circumference of the flat surface is an equipotential

Solid angle subtended by flat surface at position of charge

⇒ Flux entering through curved surface 

Also all points of circumference are at equal distance from the charge