If a wire of resistance R is stretched into double of its length, then it's resistance becomes _.
Correct answer: D. 4R
- A. R
- B. 2R
- C. 3R
- D. 4R
Explanation
As the length of wire gets doubled, the cross-sectional area will become half of its previous value because the volume of wire remains constant. Hence, we can see that the new resistance is four times the previous resistance.
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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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