Two charged spheres of radii $R_1$ and $R_2$ having equal surface charge density. The ratio of their potential is
$R_1/R_2$
$R_2/R_1$
$(R_1/R_2)^2$
$(R_2/R_1)^2$
A parallel plate capacitor is charged to a potential difference of $100\ V$ and disconnected from the source of emf. A slab of dielectric is then inserted between the plates. Which of the following three quantities change?
$(i)$ The potential difference
$(ii)$ The capacitance
$(iii)$ The charge on the plates
For shown situation of two dipoles the nature of forces between them are
Two charged spherical conductors of radii $R_1$ and $R_2$ are connected by a wire. The ratio of surface charge densities of the spheres $\sigma _1/\sigma _2$ will be
If there are $n$ capacitors in parallel connected to $V \,volt$ source, then the energy stored is equal to
Two capacitors $C_1$ and $C_2$ are are charged to $120\, V$ and $200\, V$ respectively. It is found that by connecting them together the potential on each one can be made zero . Then