NEET Properties of Semiconductors MCQs & PYQs

Practice NEET Properties of Semiconductors Questions

Question 11:

easy

Assertion (A): The temperature coefficient of resistance is positive for p-type semiconductors and negative for n-type semiconductors.

Reason (R): The effective charge carriers in p-type semiconductors are electrons and in n-type semiconductors are holes.

All semiconductors (p-type or n-type) have a negative temperature coefficient of resistance, so (A) is false. In p-type semiconductors, majority carriers are holes, and in n-type, they are electrons. Reason (R) swaps these, so it is also false. Thus, both (A) and (R) are false.

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Question 12:

easy

Assertion (A): The probability of electrons to be found in the conduction band of an intrinsic semiconductor at a finite temperature decreases exponentially with increasing band gap.

Reason (R): It is more difficult for the electrons to jump to the conduction band from the valence band if the band gap between them is large.

Assertion (A) is true: The probability of finding electrons in the conduction band is proportional to \(e^{-E_g / (2kT)}\), decreasing exponentially with band gap \(E_g\).

Reason (R) is true: A larger band gap means more energy is required for electrons to jump. Reason (R) correctly explains Assertion (A).

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