At a certain distance from a point charge the electric field is $500\,V/m$ and the potential is $3000\,V$. What is this distance......$m$

The potential function of an electrostatic field is given by $V = 2x^2$. Determine the electric field strength at the point $(2\,m, 0, 3\,m)$

A spherical charged conductor has surface charge density $\sigma $ . The electric field on its surface is $E$ and electric potential of conductor is $V$ . Now the radius of the sphere is halved keeping the charge to be constant. The new values of electric field and potential would be

In Millikan's oil drop experiment an oil drop carrying a charge $Q$ is held stationary by a potential difference $2400\,V$ between the plates. To keep a drop of half the radius stationary the potential difference had to be made $600\,V$. What is the charge on the second drop

Which of the following is true for the figure showing electric lines of force? ($E$ is electrical field, $V$ is potential)

The variation of potential with distance $R$ from a fixed point is as shown below. The electric field at $R = 5\,m$ is......$volt/m$