Three identical capacitors connected in series have net capacitance '$x$'. Then they are connected in parallel. The ratio of energy stored in series configuration to that in parallel configuration is (if both configurations are connected to the same source)

When cell of E.M.F. '$E_1$' is connected to potentiometer wire the balancing length is '$l_1$'. Another cell of E.M.F. '$E_2$' ($E_1 > E_2$) is connected along with $E_1$ so as two cells oppose each other, the balancing length is '$l_2$'. The ratio $E_1 : E_2$ is

In the following network,
$I_1 = -0.4\,\text{A}$ , $I_4 = 1\,\text{A}$ , $I_5 = 0.4\,\text{A}$
The values of $I_2$, $I_3$ and $I_6$ are respectively

A particle of charge '$q$' and mass '$m$' moves in a circular orbit of radius '$r$' with angular speed '$\omega$'. The ratio of the magnitude of its magnetic moment to that of its angular momentum depends upon