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Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R. Assertion A: Alloys such as constantan and manganin are used in making standard resistance coils. Reason R: Constantan and manganin have very small value of temperature coefficient of resistance. In the light of the above statements, choose the correct answer from the options given below.

Options

  1. ABoth A and R are true and R is the correct explanation of A
  2. BBoth A and R are true but R is NOT the correct explanation of A.
  3. CA is true but R is false.
  4. DA is false but R is true.

Correct answer

A. Both A and R are true and R is the correct explanation of A

Step-by-step solution

The alloys manganin and constantan are used for making standard resistance coils as they have high resistivity, low-temperature coefficient of resistance, ability to attain good resistance values in small size. Their resistance value would change very little with temperature. Thus, both A and R are true and R is the correct explanation of A.

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