The internal resistance of a cell of emf $4 \text{ V}$ is $0.1 \ \Omega$. It is connected to an external resistance of $3.9 \ \Omega$. The terminal voltage across the cell will be . . . . . . . (in $\text{ V}$)

When a current of $2 \ A$ flows through a resistor of $2 \ \Omega$,the terminal voltage across the cell is $E/2$. The internal resistance of the cell is ........ $\Omega$.

The $e.m.f.$ of a cell is $6 \ V$. When a current of $2 \ A$ flows through it,the potential difference across its terminals is $3 \ V$. The internal resistance of the cell is ............. $\Omega$.

$A$ battery of $24$ cells,each of emf $1.5\, V$ and internal resistance $2\, \Omega$,is to be connected to send the maximum current through a $12\, \Omega$ resistor. The correct arrangement of cells will be:

Electromotive force is actually not a force. What does it represent?

When an external resistance of $5\text{ }\Omega$ is connected across the terminals of a cell,a current of $0.25\text{ A}$ flows through it. When the $5\text{ }\Omega$ resistor is replaced by a $2\text{ }\Omega$ resistor,a current of $0.5\text{ A}$ flows through it. The internal resistance of the cell is . . . . . . $\Omega$.