The length and radius of an electric resistance of a certain wire are doubled simultaneously, then the:
Correct answer: B. Resistance will be halved and specific resistance will remain uncharged
- A. Resistance will be doubled and specific resistance will be halved
- B. Resistance will be halved and specific resistance will remain uncharged
- C. Resistance will be halved and specific resistance will be doubled
- D. Resistance and specific resistance will both remain uncharged
Explanation
Correct option is B. The formula for resistance of wire is given by: ρ = RA/l. In Specific resistance there will be no Change . Specific resistance will remain the same as it is a material property but a point to be remembered is that it depends upon temperature.
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About Current Electricity
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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