Target Exam

CUET

Subject

Physics

Chapter

Semiconductors and Electronic Devices

Question:

Read the following statements and identify the correct statements.

(A) In a semiconductor doped with trivalent impurity, the holes are the majority carriers and electrons are minority carriers.
(B) In pure semiconductors, the number of free electrons is equal to the number of holes.
(C) In a semiconductor doped with pentavalent impurity, electrons become the majority carriers and holes the minority carriers.
(D) Important electronic devices can be developed using intrinsic semiconductors.

Choose the correct answer from the options given below:

Options:

(A), (B) and (C) only

(A), (C) and (D) only

(B), (C) and (D) only

(A), (B), (C) and (D)

Correct Answer:

(A), (B) and (C) only

Explanation:

The correct answer is Option (1) → (A), (B) and (C) only

Correct statements:

☀ (A) In a semiconductor doped with trivalent impurity, the holes are the majority carriers and electrons are minority carriers.

☀ (B) In pure semiconductors, the number of free electrons is equal to the number of holes.

☀ (C) In a semiconductor doped with pentavalent impurity, electrons become the majority carriers and holes the minority carriers.

Explanation: Statement (D) is incorrect because intrinsic semiconductors have very low conductivity at room temperature, so practical electronic devices are typically made using extrinsic (doped) semiconductors.