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Question
State three factors on which the resistance of a wire depends. Explain, how does the resistance depend on the factors stated by you.
Solution
The factors on which resistance of the wire depends are :
(i) The length of the wire, resistance is directly proportional to the length of the wire.
(ii) The cross-section of the wire, resistance is inversely proportional to the cross-section of the wire.
(iii) The temperature of the wire, the resistance of wire is directly proportional to the temperature of the wire.
(iv) The material of the wire (good conductors possess less resistance.)
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