Physics (AS & A Level) · May / June 2019 · Paper 13 · Question 34

Diagram 1 shows a lamp connected to a supply through two switches. During repairs, an electrician mistakenly reverses the connections X₁ and Z₁, so that Z₁ is connected to the supply and X₁ to the other switch at Z₂, as shown in diagram 2. Which switch positions will now light the lamp?

1. AX₁ to Y₁ X₂ to Y₂
2. BX₁ to Y₁ X₂ to Z₂
3. CX₁ to Z₁ X₂ to Y₂
4. DX₁ to Z₁ X₂ to Z₂

As printed in the paper