The resistance of a metallic wire becomes 8 times when:
Correct answer: C. Length is doubled and radius is halved
- A. Length is doubled
- B. Length is trippled
- C. Length is doubled and radius is halved
- D. Length is halved and radius is doubled
Explanation
The correct option is: c) Length is doubled and radius is halved If the length of the wire is doubled (2L) and the radius is halved (R/2), the resistance becomes 8 times its original value. This option is correct. solution A = πr² A = π(r/2)² A = πr²/8
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Steady current relates charge flow to potential difference, resistance and resistivity, including how temperature changes a conductor's resistance. Sources with internal resistance have terminal voltage below their emf when delivering current, and maximum power output occurs under a specific load condition rather than at zero resistance.
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