# College Assignment question need help!

#### unknown93

Joined Feb 13, 2013
2
The question is

An amplifier has an open-loop gain off 99db's, if 10% of the output signal is fed-back into the input in antiphase with input signal, determine:

(A) From the first principles the transfer function for the amplifier and
(B) hence determine the closed-loop gain of the amplifier

thanks

#### MrChips

Joined Oct 2, 2009
28,471
This is not a homework assignment service provider.

#### #12

Joined Nov 30, 2010
18,224
We do have a Homework section. I'll ask to have this moved to the proper forum.

#### WBahn

Joined Mar 31, 2012
28,464
What efforts have you made to solve the problem (never forget, it is YOUR problem)?

Once you show your efforts, we will have something to hook into and help you make progress.

#### unknown93

Joined Feb 13, 2013
2
so some sort of formulae would help

thanks

#### MrChips

Joined Oct 2, 2009
28,471
Geeze, you don't get it. There is no formula.
You have to work through the equations yourself.
We don't know. This is your problem. Show us what you think is the proper approach.
Start by drawing a diagram.

#### WBahn

Joined Mar 31, 2012
28,464