A light-dependent resistor (LDR) has a low resistance when the light intensity is high and a high resistance in darkness.
(a)[2]
Sketch a graph showing resistance (y-axis) against light intensity (x-axis) for an LDR.
(b(i))[1]
Complete the circuit in Fig. 5.1 by adding the symbol for a light-dependent resistor (LDR).
(b(ii))[3]
Explain why the lamp is off in light conditions and on in darkness. Use ideas about potential difference (p.d.) in your answer.
Worked solution & mark scheme
This 6-mark question has a full step-by-step worked solution and mark scheme. One marking point: “y-axis labelled resistance AND x-axis labelled light intensity” …