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

Resistance exhibits temperature dependence:
- Metals display a positive temperature coefficient. Resistance rises with temperature due to increased electron collision frequency.
- Semiconductors exhibit a negative temperature coefficient. Elevated temperatures create more charge carriers, thus decreasing resistance.
- The type of charge carrier does not account for this phenomenon.
Consequently, both assertions are valid, but Reason (R) does not adequately explain Assertion (A).