If length of the wire becomes two times to the original value and area becomes one half to its original value, then resistance of the wire becomes:
Correct answer: B. Four times
- A. Double
- B. Four times
- C. One half
- D. One fourth
Explanation
R= ρL/AL' = 2LA' = 1/2AR' = 2L/(1/2A)R' = 4L/AR' = 4 R
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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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