CAPE Physics Unit 2 · 2013 · Paper 2 · Question 5(b)(i)

Figure 5 shows a circuit implementation with an open-loop op-amp comparator, an LDR, logic circuit in dashed box P, switching amplifier, and relay.

In this circuit, the open loop operational amplifier is used to compare the surrounding lighting level with a preset value. Explain how this is done.

This question uses a figure or table from the paper — you'll see it when you practise.