If an amplifier circuit has negative feedback, then gain:

This question was previously asked in
RRB ALP Electronics Mechanic 23 Jan 2019 Official Paper (Shift 2)
View all RRB ALP Papers >
  1. increases and decreases
  2. stays constant
  3. increases
  4. decrease

Answer (Detailed Solution Below)

Option 4 : decrease
Free
General Science for All Railway Exams Mock Test
2.1 Lakh Users
20 Questions 20 Marks 15 Mins

Detailed Solution

Download Solution PDF

Transistor as an Amplifier

F1 Madhuri Engineering 16.01.2023 D5

A transistor is a 3-terminal device i.e. base, collector, and emitter 

When the base-emitter junction is forward-biased and the collector-emitter is reversed-biased, the transistor acts as an amplifier.

The working of the amplifier is based on negative feedback.

In a negative feedback circuit, some part of the output is fed back to the input.

Explanation

F2 Savita Engineering 31-3-23 D1

The closed loop gain for negative feedback is given by:

\(A_f={A\over 1+AM}\)

where, Af = Closed loop gain

A = Open loop gain

M = Feedback factor

So, when negative feedback amplifier, the gain reduces by the factor (1+AM)

Latest RRB ALP Updates

Last updated on Jun 2, 2025

-> The RRB NTPC Admit Card 2025 has been released on 1st June 2025 on the official website.

-> Railway Recruitment Board activated the RRB ALP application form 2025 correction link, candidates can make the correction in the application form till 31st May 2025. 

-> The Railway Recruitment Board (RRB) has released the official RRB ALP Notification 2025 to fill 9,970 Assistant Loco Pilot posts.

-> The Railway Recruitment Board (RRB) has released the official RRB ALP Notification 2025 to fill 9,970 Assistant Loco Pilot posts.

-> The official RRB ALP Recruitment 2025 provides an overview of the vacancy, exam date, selection process, eligibility criteria and many more.

->The candidates must have passed 10th with ITI or Diploma to be eligible for this post. 

->The RRB Assistant Loco Pilot selection process comprises CBT I, CBT II, Computer Based Aptitude Test (CBAT), Document Verification, and Medical Examination.

-> This year, lakhs of aspiring candidates will take part in the recruitment process for this opportunity in Indian Railways. 

-> Serious aspirants should prepare for the exam with RRB ALP Previous Year Papers.

-> Attempt RRB ALP GK & Reasoning Free Mock Tests and RRB ALP Current Affairs Free Mock Tests here

Get Free Access Now
Hot Links: teen patti sweet teen patti master update teen patti gold download teen patti real