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प्रश्न
Define the term resistivity and state its S.I. unit. Which will have higher resistivity a conductor or an insulator.
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उत्तर
The resistivity of a substance is the resistance of a wire of that substance of unit length and unit area of cross-section. Its S. I. unit is ohm × m. An insulator will have higher resistivity.
संबंधित प्रश्न
In series combination which remains constant?
(a) Voltage
(b) Current
(c) Both current and voltage
(d) Both are variables
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- Series
- Parallel
- Mixed arrangement
- None of the above
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its diameter is tripled?
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Two resistors having 2Ω and 3Ω resistance are connected—(i) in series, and (ii) in parallel. Find the equivalent resistance in each case.
