Welcome to Junction Transistor NEET MCQ, In this carefully crafted collection of multiple-choice questions (MCQs), each query is thoughtfully paired with both the correct answer and a comprehensive explanation. Specifically tailored for NEET (National Eligibility-cum-Entrance Test) preparation, these MCQs serve not only to test your knowledge of junction transistors but also to provide you with an in-depth understanding of this essential topic.
A bipolar junction transistor is a semiconductor device with three terminals and two p-n junctions. The three terminals are named as the base, emitter and collector. The small-amplitude signal applied at the base is amplified at the collector. The Bipolar Junction transistor is of two types, NPN transistor and PNP transistor, based on the doping types of the three terminals.
1. A junction transistor consists of how many p-n junctions?
Answer:
Explanation:
A junction transistor has two p-n junctions, making a total of three layers.
2. Which configuration among the following provides the highest input impedance for a transistor?
Answer:
Explanation:
The Common Collector configuration provides the highest input impedance among the given configurations.
3. In a npn transistor, the arrow in the symbol points:
Answer:
Explanation:
In the symbol for an npn transistor, the arrow points outward, indicating the direction of conventional current flow.
4. Which layer is the thinnest in a junction transistor?
Answer:
Explanation:
The base layer is the thinnest in a junction transistor.
5. The transistor configuration most commonly used for amplification is:
Answer:
Explanation:
The Common Emitter configuration is widely used for amplification purposes because of its phase inversion and good amplification properties.
6. In a transistor, the majority carriers in the emitter region are:
Answer:
Explanation:
Depending on whether it's npn or pnp, the emitter region's majority carriers can be electrons or holes respectively.
7. The cutoff frequency of a transistor is the frequency at which the current gain:
Answer:
Explanation:
The cutoff frequency is the frequency at which the current gain drops to one.
8. Which region of a transistor is most heavily doped?
Answer:
Explanation:
The emitter region is the most heavily doped to provide a high concentration of charge carriers.
9. The output phase difference in a Common Emitter configuration, between input and output is:
Answer:
Explanation:
In a Common Emitter configuration, the output is inverted, leading to a phase difference of 180 degrees.
10. A transistor can act as a:
Answer:
Explanation:
Transistors can be utilized in various roles, including amplification, switching, and oscillation.
11. In a pnp transistor, the n-type semiconductor acts as:
Answer:
Explanation:
In a pnp transistor, the n-type material is sandwiched between two p-type materials, making it the base.
12. The base-collector junction of a transistor is:
Answer:
Explanation:
To allow the transistor to function properly, the base-collector junction is generally reverse biased.
13. The role of the base in a transistor is to:
Answer:
Explanation:
The base in a transistor acts as a control, modulating the flow of charge carriers between the emitter and collector.
14. A transistor is said to be in active mode when:
Answer:
Explanation:
For amplification, a transistor operates in active mode with the described biasing conditions.
15. The power dissipation in a transistor is given by:
Answer:
Explanation:
Power dissipation is the product of the voltage drop across the collector-emitter junction and the current flowing through it.