The resistance of a wire of length L and radius r is R. Which one of the following would provide a wire of the same material of resistance R/2 :

The resistance of a wire of length L and radius r is R. Which one of the following would provide a wire of the same material of resistance R/2 :

(A) Using a wire of same radius and twice the length
(B) Using a wire of same radius and half length
(C) Using a wire of same length and twice the radius
(D) Using a wire of same length and half the radius

Correct Answer : Option (B) Using a wire of same radius and half length

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