The electric resistance of a certain wire of iron is $R$. If its length and radius are both doubled, then
  • A
    The resistance will be doubled and the specific resistance will be halved
  • B
    The resistance will be halved and the specific resistance will remain unchanged
  • C
    The resistance will be halved and the specific resistance will be doubled
  • D
    The resistance and the specific resistance, will both remain unchanged
AIPMT 2004, Easy
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