(a(i))[1]
Show that the potential at the inverting input of the op-amp equals $+1.0\,\text{V}$.
(a(ii))[4]
Explain why the potential difference across resistor $R$ is $+5\,\text{V}$ when $V_{IN}$ exceeds $1.0\,\text{V}$ and is zero when $V_{IN}$ is below $1.0\,\text{V}$.
(b(i))[2]
On the axes in Fig. 10.2, sketch how the output potential $V_{OUT}$ varies with time $t$.
(b(ii))[1]
Suggest one use for this type of circuit.