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Question
How does the resistance of a wire depend on its length? Give a reason for your answer.
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Solution
Resistance of a wire is directly proportional to the length of the wire.
R ∝ I
The resistance of a conductor depends on the number of collisions which the electrons suffer with the fixed positive ions while moving from one end to the other end of the conductor. Obviously the number of collisions will be more in a longer conductor as compared to a shorter conductor. Therefore, a longer conductor offers more resistance.
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