A test circuit has a 12 V supply, an 8.0 Ω resistor and a second resistor, all connected in series. The circuit works correctly only if the potential difference across the 8.0 Ω resistor is at least 3.5 V. The second resistor is chosen so that, with the 12 V supply, the potential difference across the 8.0 Ω resistor is 4.0 V.
Calculate the resistance of the second resistor.
The 12 V supply is replaced by a 9.0 V battery. The second resistor is not changed.
Determine whether the circuit still works correctly.
94 exam-style questions on AQA GCSE Physics 2.2 Series and parallel circuits, covering 2.2 Series and parallel circuits. Each one has a worked solution and a mark scheme showing where the marks go.