Two charges $ + 3.2\, \times \,{10^{ - 19}}\,C$ and $ - 3.2\, \times \,{10^{ - 19}}\,C$ kept $2.4\,\mathop A\limits^o $ apart forms a dipole. If it is kept in uniform electric field of intensity $4\, \times \,{10^{5\,}}\,volt/m$ then what will be its potential energy in stable equilibrium
$ + 3 \times {10^{ - 23\,}}\,J$
$ -3 \times {10^{ - 23\,}}\,J$
$ -6 \times {10^{ - 23\,}}\,J$
$ -2 \times {10^{ - 23\,}}\,J$
In infinite long uniformly charged string is placed along $z-$ axis. Its linear charge density is $\lambda $. A point charge $q$ is moved from position $(a, 0, 0)$ to $(2a, 0, 0)$ then work done will be
A wheel having mass $m$ has charges $+q $ and $-q$ on diametrically opposite points. It remains in equilibrium on a rough inclined plane in the presence of uniform vertical electric field $E =$
The electric flux from a cube of edge $l$ is $\phi $. If an edge of the cube is made $2l$ and the charge enclosed is halved, its value will be
An infinite number of identical capacitors each of capacitance $1 \mu F$ are connected as shown in the figure. Then, the equivalent capacitance between $A$ and $B$ is .......... $\mu F$
Figures below show regular hexagons, with charges at the vertices, In which of the following cases the electric field at the centre is not zero.