Electrostatics · Physics · MHT CET (Biology)

A hollow charged metal sphere has a radius ' $r$ '. If the potential difference between its surface and a point at a distance ' 3 r ' from the centre is ' $v$ ', then the electric field intensity at a distance ' $3 r$ ' is

In the diagram, the total electric flux through the closed surface ' S ' is

[Given $\mathrm{q}=$ charge

$\varepsilon_0=$ permittivity of free space]