Physics (AS & A Level) · May / June 2020 · Paper 13 · Question 36

The wire of a heating element has resistance R. The wire breaks and is replaced by a different wire. Data for the original wire and for the replacement wire are shown in the table. | | length | diameter | resistivity of metal | | original wire | l | d | ρ | | replacement wire | l | 2d | 2ρ | What is the resistance of the replacement wire?

1. AR/4
2. BR/2
3. CR
4. D2R

As printed in the paper