A large insulated sphere of radius ' $r$ ', charged with ' $Q$ ' units of electricity, is placed in contact with a small insulated uncharged sphere of radius ' R ' and is then separated. The charge on the smaller sphere will now be

The wrong statement out of the following statements is

The potentials at points A and B are $\mathrm{V}_{\mathrm{A}}$ and $\mathrm{V}_{\mathrm{B}}$ respectively for the charges $+q$ and $-q$ placed at distances ' $x$ ' each from points $A$ and $B$ as shown in figure. The distance between points $A$ and B is ' y '. The net potential $\left(\mathrm{V}_{\mathrm{A}}-\mathrm{V}_{\mathrm{B}}\right)$ is proportional to

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