Question

Assertion (A): The temperature coefficient of resistance is positive for metals and negative for p-type semiconductors.
Reason (R): The charge carriers in metals are negatively charged, whereas the majority charge carriers in p-type semiconductors are positively charged.

• A. If both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
• B. If both Assertion (A) and Reason (R) are true and Reason (R) is not the correct explanation of Assertion (A).
• C. If Assertion (A) is true and Reason (R) is false.
• D. If both Assertion (A) and Reason (R) are false.

Hint:

For metals, resistance increases with temperature, whereas for semiconductors, resistance decreases with temperature.

Answer 1

The Correct Option is B

Temperature Dependence of Resistance:
- Metals have a positive temperature coefficient because resistance increases with temperature due to more frequent electron collisions.
- Semiconductors have a negative temperature coefficient as increasing temperature generates more charge carriers, reducing resistance.
- The nature of charge carriers does not explain this behavior.
Thus, both statements are true, but Reason (R) does not correctly explain Assertion (A).