(a)[2]
State two effects that negative feedback has on the gain of an amplifier that uses an operational amplifier (op-amp).
(b(i))[2]
Fig. 9.1 shows an incomplete circuit diagram of a non-inverting amplifier that uses an ideal op-amp. Complete Fig. 9.1 and label both the input and the output.
(b(ii))[2]
Calculate the resistance of resistor $R$ so that the non-inverting amplifier produces a voltage gain of $15$.
(c)[2]
On Fig. 9.2, sketch a graph to show how the output potential $V_{OUT}$ varies with input potential $V_{IN}$. Consider input potentials from $0$ to $+1.0\,\text{V}$.
(d)[2]
The output from the amplifier circuit in Fig. 9.1 can be linked to a relay. State and explain one use of a relay.