A soft, electrically-conducting cylindrical sample has resistance $R$. It is rolled out so that its length becomes twice as great, while its volume remains constant. What is its new resistance?
- A$\frac{R}{2}$
- B$R$
- C$2R$
- D$4R$
Physics 9702 · AS & A Level · Resistance and resistivity
A soft, electrically-conducting cylindrical sample has resistance $R$. It is rolled out so that its length becomes twice as great, while its volume remains constant. What is its new resistance?