The electric field at a distance $\frac{3R}{2}$ from the centre of a charged conducting spherical shell of radius $R$ is $E.$ The electric field at a distance $\frac{R}{2}$ from the centre of the sphere is
$\frac{E}{2}$
$E$
$\frac{E}{3}$
Zero
Obtain the expression of electric field by ......
$(i)$ infinite size and with uniform charge distribution.
$(ii)$ thin spherical shell with uniform charge distribution at a point outside it.
$(iii)$ thin spherical shell with uniform charge distribution at a point inside it.
An early model for an atom considered it to have a positively charged point nucleus of charge $Ze$, surrounded by a uniform density of negative charge up to a radius $R$. The atom as a whole is neutral. For this model, what is the electric field at a distance $r$ from the nucleus?
Obtain the expression of electric field at any point by continuous distribution of charge on a $(i)$ line $(ii)$ surface $(iii)$ volume.
The electric field $E$ is measured at a point $P (0,0, d )$ generated due to various charge distributions and the dependence of $E$ on $d$ is found to be different for different charge distributions. List-$I$ contains different relations between $E$ and $d$. List-$II$ describes different electric charge distributions, along with their locations. Match the functions in List-$I$ with the related charge distributions in List-$II$.
List-$I$ | List-$II$ |
$E$ is independent of $d$ | A point charge $Q$ at the origin |
$E \propto \frac{1}{d}$ | A small dipole with point charges $Q$ at $(0,0, l)$ and $- Q$ at $(0,0,-l)$. Take $2 l \ll d$. |
$E \propto \frac{1}{d^2}$ | An infinite line charge coincident with the x-axis, with uniform linear charge density $\lambda$ |
$E \propto \frac{1}{d^3}$ | Two infinite wires carrying uniform linear charge density parallel to the $x$-axis. The one along ( $y=0$, $z =l$ ) has a charge density $+\lambda$ and the one along $( y =0, z =-l)$ has a charge density $-\lambda$. Take $2 l \ll d$ |
plane with uniform surface charge density |
Obtain Coulomb’s law from Gauss’s law.