A wire of resistance 6 Ω is stretched to thrice its original length. New resistance is MCQ with Answer and Explanation

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A wire of resistance 6 Ω is stretched to thrice its original length. New resistance is

A. 54 Ω

B. 36 Ω

C. 2 Ω

D. 18 Ω

Answer: Option A

Solution (By JKSSB Mock Tests)

R ∝ L² (volume constant). L'=3L => R' = 3² × 6 = 9×6 = 54 Ω. Generally, R' = n² R for stretching n times. Important concept.

This question belongs to: Science Physics

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Correct Answer: Option C

Explanation:
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This question belongs to: Science Physics

Question #2

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Correct Answer: Option A

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Correct Answer: Option A

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