Question

Assertion :The resistance of 49 bulbs will be more then 50 bulbs in parallel. Reason: Temperature coefficient constant of a resistance is very small

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Both Assertion and Reason are incorrect

Answer 1

The correct option is B Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion

When 50 bulbs in parallel , the equivalent resistance $R_{50}=R/50$ where $R=$ resistance of each bulb.
When 49 bulbs in parallel , the equivalent resistance $R_{49}=R/49$
Thus, $R_{49}>R_{50}$
The resistivity of constantan wire is constant over a wide range of temperature and it has low temperature coefficient of resistance.
Ans: B