$A$ current of $2\,A$ flows through a $2\,\Omega$ resistor when connected across a battery. The same battery supplies a current of $0.5\,A$ when connected across a $9\,\Omega$ resistor. The internal resistance of the battery is

The actual value of resistance $R$,shown in the figure is $30\,\Omega$. This is measured in an experiment as shown using the standard formula $R_{measured} = \frac{V}{I}$,where $V$ and $I$ are the readings of the voltmeter and ammeter,respectively. If the measured value of $R$ is $5\%$ less than the actual value,then the internal resistance of the voltmeter is ................. $\Omega$.

In the circuit shown in the figure,the currents in different branches and the value of one resistor are given. Then,the potential at point $B$ with respect to point $A$ is $.......V$.

The effective resistance between $A$ and $B$ of the shown network,where the resistance of each resistor is $R$,is

$A$ battery having $e.m.f.$ $5\,V$ and internal resistance $0.5\,\Omega$ is connected with a resistance of $4.5\,\Omega$. The voltage at the terminals of the battery is ............. $V$.

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 ${H_2} = 0.09\,kg/{m^3}$)