A circuit diagram contains a battery linked to a resistor $R$. The battery also has an internal resistance, shown as resistor $r$. A second resistor, the same as $R$, is then placed in parallel with $R$. Which row gives the changes in the potential difference (p.d.) across $r$ and in the current reading on the ammeter when the second resistor is added?
Physics 9702 · AS & A Level · Momentum and Newton's laws of motion