(a(i))[2]
State the meaning of negative feedback.
(a(ii))[2]
State two effects of negative feedback on an amplifier using an operational amplifier (op-amp).
(b)
Fig. 9.1 shows a circuit for an amplifier used with a microphone. The output potential difference $V_{\text{OUT}}$ is $4.4\,\text{V}$ when the potential at point $P$ is $62\,\text{mV}$. Determine:
(b(i))[1]
State the gain of the amplifier.
(b(ii))[2]
Determine the value of resistance of resistor $R$.
(c)[3]
The maximum potential difference produced by the microphone at point $P$ on Fig. 9.1 is $95\,\text{mV}$. The operational amplifier may be powered by either $\pm 5\,\text{V}$ or $\pm 9\,\text{V}$. State which power supply should be used. Support your answer with a numerical justification.