Question

Match the LIST-I with LIST-II

LIST-I (Configuration of Bipolar Transistors)		LIST-II (Characteristics)
A.	Common Base	I.	Current Gain but no Voltage Gain
B.	Common Emitter	III.	Both Current and Voltage Gain
C.	Common Collector	II.	Voltage Gain but no Current Gain

Choose the correct answer from the options given below:

• A. A - I, B - II, C - III
• B. A - II, B - III, C - I
• C. A - I, B - III, C - II
• D. A - III, B - II, C - I

Hint:

A simple way to remember BJT configurations: - **Common Emitter (CE):** The all-rounder. Good voltage and current gain. Inverts the signal. - **Common Collector (CC):** The "buffer". High current gain, unity voltage gain. Used for impedance matching. - **Common Base (CB):** The "current follower". Unity current gain, high voltage gain. Used for high-frequency applications.

Answer 1

The Correct Option is B

Step 1: Evaluate the properties of each BJT configuration.- A. Common Base (CB): Exhibits low input impedance and high output impedance. Its current gain (\(\alpha\)) is marginally below 1, but it offers substantial voltage gain. Consequently, it provides "Voltage Gain but no Current Gain." This corresponds to II.- B. Common Emitter (CE): The most prevalent configuration, featuring medium input and output impedance. It delivers considerable gain for both current (\(\beta\)) and voltage. Thus, it offers "Both Current and Voltage Gain." This corresponds to III.- C. Common Collector (CC): Referred to as an emitter follower, this configuration presents high input impedance and low output impedance. Its voltage gain approximates 1. It achieves high current gain (\(\beta+1\)). Therefore, it provides "Current Gain but no Voltage Gain." This corresponds to I.
Step 2: Determine the correct matching order.Based on the preceding analysis:- A matches II.- B matches III.- C matches I.This sequence aligns with option (2).