$A$ battery of $e.m.f.$ $10\, V$ and internal resistance $0.5\, \Omega$ is connected across a variable resistance $R$. The value of $R$ for which the power delivered in it is maximum is given by ......... $\Omega$.

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 below,the cell has an $e.m.f.$ of $10\,V$ and internal resistance of $1\,\Omega$. The other resistances are shown in the figure. The potential difference ${V_A} - {V_B}$ is ................ $V$.

Which of the four resistances $P, Q, R$ and $S$ generate the greatest amount of heat when a current flows from $A$ to $B$?

If the power dissipated in the $3\,\Omega$ resistor is $27\,W$,then what is the power dissipated in the $2\,\Omega$ resistor (in $,W$)?

When a current of $16 \, A$ is passed through a $NaCl$ cell for $10 \, min$,what mass of $Na$ (in $g$) is deposited?