In the figure,the current through the $3\,\Omega$ resistor is $0.8\,A$. Then,the potential drop across the $4\,\Omega$ resistor is ........... $V$.

In the circuit shown,$n$-identical resistors $R$ are connected in parallel $(n > 1)$ and the combination is connected in series to another resistor $R_0$. In the adjoining circuit,$n$ resistors of resistance $R$ are all connected in series along with $R_0$. The batteries in both circuits are identical and the net power dissipated in the $n$ resistors in both circuits is the same. The ratio $R_0 / R$ is

In how much time will one litre of ${H_2}$ be collected by a $5\, A$ current? (Given: $Z = 1 \times {10^{ - 8}}\,kg/C$ and density of ${H_2} = 0.09\,kg/{m^3}$)

Which arrangement of four identical resistances should be used to draw maximum energy from a cell of voltage $V$?

In the adjoining circuit,the potential difference across $3\,\Omega$ is ................ $V$.

It takes $15 \ min$ to heat water in an electric kettle. If the length of the heating coil is reduced to $2/3$ of its original length,how many minutes will it take to heat the same amount of water?