The minimum value of $|z-1|+|z-5|$ is

When a current of $2\,A$ flows in a battery from negative to positive terminal,the potential difference across it is $12\,V$. If a current of $3\,A$ flows in the opposite direction,the potential difference across the terminals of the battery is $15\,V$. The emf of the battery is ............... $V$.

If the charge on a body is increased by $2 \ C$,the energy stored in it increases by $21 \%$. The original charge on the body in coulomb is

The angle of incidence at which reflected light is totally polarized for reflection from air to glass (refractive index $n$) is

$A$ fully charged capacitor $C$ with initial charge $q_0$ is connected to a coil of self-inductance $L$ at $t = 0$. The time at which the energy is stored equally between the electric and the magnetic fields is

If $1, \log_9(3^{1-x} + 2), \log_3(4 \cdot 3^x - 1)$ are in $A.P.$,then $x$ equals