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Current Electricity — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsCurrent Electricity1 Mark
MCQ
Constantan wire is used for making standard resistance, because it has:
  • A
    High melting point.
  • B
    Low specific resistance.
  • C
    High specific resistance.
  • D
    Negligible temperature coefficient of resistance.
✓

Answer

  1. Negligible temperature coefficient of resistance.

Explanation:

Constantan is a copper-nickel alloy. Its main feature is its resistivity, which is constant over a wide range of temperatures. Thus it has low temperature coefficient of resistance.that's why it is used for making of standard resistances.

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