# MCQs on PN junction diode for NEET 2020

NEETÂ  Physics is the scoring paper in the medical entrance examination. Here, you will discover the NEET Physics MCQ Questions for all Concepts as per the latest syllabus. Practice more on a regular basis with these NEET Physics objective questions on air pollution and improve your subject knowledge & problem-solving skills along with time management. NEET Physics PN junction diode Multiple Choice Questions make you feel confident in answering the question in the exam & increases your scores to high.

## MCQs on PN junction diode

1. In a PN junction with no external voltage, the electric field between acceptor and donor ion is called a
(a) Peak
(b) Barrier
(c) Threshold
(d) Path

2. In a PN junction the potential barrier is due to the charges on either side of the junction, these charges are
(a) Majority carriers
(b) Minority carriers
(c) Both (a) and (b)
(d) Fixed donor and accepter ions

Answer: (d) Fixed donor and accepter ions

3. The capacitance of a reverse-biased PN junction
(a) Increases as reverse bias is increased
(b) Decreases as reverse bias is increased
(c) Increases as reverse bias is decreased
(d) Is significantly low

Answer: (c) Increases as reverse bias is decreased

4. For a PN junction diode, the current in reverse bias maybe
(a) Few milliamperes
(b) Between 0.2 A and 15 A
(c) Few amperes
(d) Few micro or nano amperes

Answer: (d) Few micro or nano amperes

5. When PN junction is in forward bias, by increasing the battery voltage
(a) Circuit resistance increases
(b) Current through P_N junction increases
(c) Current through P_N junction decreases
(d) None of the above

Answer: (b) Current through P_N junction increases

6. When a PN junction is reverse biased
(a) Holes and electrons tend to concentrate towards the junction
(b) The barrier tends to break down
(c) Holes and electrons tend to move away from the junction
(d) None of these

Answer: (c) Holes and electrons tend to move away from the junction

7. A PN junction
(a) Has low resistance in forward as well as reverse directions
(b) Has high resistance in forward as well as reverse directions
(c) Conductors in the forward direction only
(d) Conducts in the reverse direction only

Answer: (c) Conductors in the forward direction only

8. A PN junction is said to be forward-biased when
(a) The positive terminal of the battery is connected to P-side and the negative side to the N-side
(b) Junction is earthed
(c) N-side is connected directly to the p-side
(d) The positive terminal of the battery is connected to N-side and the negative side to the P-side.

Answer: (a) The positive terminal of the battery is connected to P-side and the negative side to the N-side

9. PN junction failure below 5 V is caused primarily by
(a) Avalanche breakdown
(b) Zener breakdown
(c) Either (a) or (b)
(d) None of the above