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Q1. | Copper wire of certain length and resistance is drawn out to three times its length without change in volume, the new resistance of wire becomes |

A. | 1/9 times [Wrong Answer] |

B. | 3 times [Wrong Answer] |

C. | 9 times [Correct Answer] |

D. | unchanged [Wrong Answer] |

View Answer
Explanation:-
Answer : CDiscuss it below :KARTHIK Karthik Said on 2018-04-10 05:57:12When a wire is stretched, its volume will remain the same. Since Volume = Area x length, given that length has increased three times, the area will be decreased by 3. So, new length = 3L. New Area = A/3 Resistance is proportional to Length/Area. New resistance is proportional to 3L/(A/3) New resistance = 9R !! OOPS Login [Click here] is required to post your answer/resultHelp other students, write article, leave your comments |

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