The resistance of a wire is 10 Ω. What is the new resistance if the length of the wire is doubled?
Correct answer: A. 20 Ω
- A. 20 Ω
- B. 40 Ω
- C. 1/2 Ω
- D. 1/4 Ω
Explanation
Assuming the wire is simply replaced by one twice as long with the same area and material, resistance is directly proportional to length. Therefore, doubling the length will double the resistance from 10 Ω to 20 Ω.
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