If a metal cube of side $5\, cm$ has a charge of $6$ microcoulombs, then the surface charge density is

A square plate of side $'a'$ is placed in $xy$ plane having centre at origin if charge density of square plate is $\sigma  = xy$ then. Total charge on the plate will be

What are linear, surface and volume distribution of charge ?

Charge is distributed within a sphere of radius $R$ with a volume charge density $\rho (r) = \frac{A}{{{r^2}}}{e^{ - 2r/a}}$ where $A$ and $a$ are constants. If $Q$ is the total charge of this charge distribution, the radius $R$ is.

Three concentric metallic spherical shells of radii $R, 2 R, 3 R$, are given charges $Q_1, Q_2, Q_3$, respectively. It is found that the surface charge densities on the outer surfaces of the shells are equal. Then, the ratio of the charges given to the shells, $Q_1: Q_2: Q_3$, is

A semicircular ring of radius $'a'$ has charge density $\lambda  = {\lambda _0}\,\cos \,\theta $ where ${\lambda _0}$ is constant and $'\theta'$ is shown in figure. Then total charge on the ring is