(a)[1]
Name the component that makes up the output device.
(b)[2]
An operational amplifier (op-amp) serves as the processing unit. Describe the role of this processing unit.
(c(i))[1]
State the purpose of resistors C and D.
(c(ii))[1]
State the purpose of resistor B.
(d(i))[1]
The output device in Fig. 9.1 is replaced so that the new output device can be used to switch on a high-voltage circuit. State the component used in the new output device.
(d(ii))[2]
Draw on Fig. 9.2 to show how the component in (i), together with a diode, is connected so that the high voltage can be switched on when the output of the op-amp is negative.