The length and radius of electric resistance of a certain wire are doubled simultaneously, then the _.
Correct answer: B. Resistance will be halved and the specific resistance will remain unchanged
- A. Resistance will be doubled and specific resistance will be halved
- B. Resistance will be halved and the specific resistance will remain unchanged
- C. Resistance will be halved and the specific resistance will be doubled
- D. Resistance and specific resistance will both remain uncharged
Explanation
R= ρ L/A Ρ is a constant so it won't change. l/r^2= 2L/(2r)^2 2L/4r^2 ½ resistance and specific resistance will remain unchanged so B.
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