logo

Ask Questions, Get Answers

 
X
 Search
Want to ask us a question? Click here
Browse Questions
Ad
0 votes

When negative voltage feedback is applied to an amplifier of gain 150, the overall gain falls to 15. Find the fraction of the output that is feedback to the input.

$(a)\;1.06 \\ (b)\;0.06 \\ (c)\;0.01 \\ (d)\;0.03 $
Can you answer this question?
 
 

1 Answer

0 votes
$A= 150$
$A_f =15$
$A_f= \large\frac{A}{1+\beta A}$
$15 =\large\frac{150}{1+150 \beta}$
$15 +2250 \beta =150$
$2250 \beta =150-15$
$\qquad=135$
$\beta= \large\frac{135}{2250}$
$\qquad= 0.06$
answered Jan 28, 2014 by meena.p
edited Jul 14, 2014 by balaji.thirumalai
 

Related questions

Ask Question
student study plans
x
JEE MAIN, CBSE, NEET Mobile and Tablet App
The ultimate mobile app to help you crack your examinations
Get the Android App
...