Ohm's Law, Resistivity & Temperature
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.
Show answer and solution
Answer: (a)
- Assertion: constantan and manganin are used for standard resistance coils. True.
- Reason: they have a very small temperature coefficient of resistance, so their resistance stays nearly constant. True.
- This small is exactly why they are chosen, so R explains A.
- So the answer is (a).