The open-loop voltage gain of an amplifier is given by [A_{v}=frac{10^{4}}{left(1+j frac{f}{5 times 10^{3}} ight)^{2}left(1+j frac{f}{5 times

The open-loop voltage gain of an amplifier is given by

\[A_{v}=\frac{10^{4}}{\left(1+j \frac{f}{5 \times 10^{3}}\right)^{2}\left(1+j \frac{f}{5 \times 10^{5}}\right)}\]

(a) Assuming the feedback transfer function is not a function of frequency, determine the frequency at which the phase of the loop gain is 180 degrees.

(b) At what value of \(\beta\) will the feedback amplifier become unstable?

(c) Using the value of \(\beta\) found in part (b), what is the low-frequency closed-loop gain?

(d) Is the closed-loop feedback system stable for smaller or larger values of \(\beta\) ?