In a copper voltameter,the mass deposited in $30\, \text{s}$ is $m\, \text{g}$. If the current-time graph is as shown in the figure,the Electrochemical Equivalent $(ECE)$ of copper is:

$A$ storage battery of $emf$ $8.0\; V$ and internal resistance $0.5\; \Omega$ is being charged by a $120\; V$ $DC$ supply using a series resistor of $15.5\; \Omega$. What is the terminal voltage of the battery during charging? What is the purpose of having a series resistor in the charging circuit?

In the given circuit,if the current flowing through the $5 \Omega$ resistor is $0.5 \text{ A}$,then the value of $E$ is: (in $\text{ V}$)

Consider a circuit where a cell of emf $E_0$ and internal resistance $r$ is connected across the terminals $A$ and $B$ as shown in the figure. The value of $R$ for which the power generated in the circuit is maximum is given by

$A$ $3\,V$ battery with negligible internal resistance is connected in a circuit as shown in the figure. The current $I$ in the circuit will be ............. $A$.

The diagram shows a circuit. Choose the incorrect statement.