A cell is joined to a resistor with resistance $3.00\,\Omega$. The current through the resistor is $1.00\,\text{A}$. An identical second resistor is then connected in parallel. The current rises to $1.93\,\text{A}$. Determine the e.m.f. $E$ and internal resistance $r$ of the cell.
Physics 9702 · AS & A Level · Practical circuits