Soft cylindrical electrical conducting wire has resistance R. It is stretched so that its length is doubled but its radius stays constant. What would be the new resistance?
Correct answer: D. 2R
- A. R/2
- B. R
- C. 4R
- D. 2R
Explanation
As R = ρL/A R ∝ L If length is doubled then R is also doubled, so R =2R. Hence, option D is correct
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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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