Answer: According to Ohm’s Law ($I = \fracVR$), current is directly proportional to the potential difference if resistance is constant. If the potential difference ($V$) is halved ($\fracV2$), the current ($I$) will also become half of its original value.

Answer: A battery (or a cell) helps maintain a potential difference across a conductor. It uses chemical reactions inside it to create a potential difference between its terminals.

Answer: Since they are connected in parallel to the mains supply ($220 \text V$), both lamps operate at their rated voltage.

$$\frac1R_p = \frac11 + \frac11000 + \frac110^6$$ $$\frac1R_p = 1 + 0.001 + 0.000001 \approx 1.001$$ $$R_p = \frac11.001 \approx 0.999 \ \Omega \approx 1 \ \Omega$$