CAPE Physics Unit 2 · 2015 · Paper 1 · Question Q17

With the LDR in complete darkness, the voltage across it is 10\text{ V}. When fully illuminated, the voltage across it drops to 3\text{ V}. What will be the current in the 2\text{ k}\Omega resistor at that time? (Assume that when the LDR is in complete darkness, its resistance is infinite.)

1. (A)0.35\text{ mA}
2. (B)3.5\text{ mA}
3. (C)5\text{ mA}
4. (D)7\text{ mA}

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