Which of the following correctly describes the standard domestic electricity supply in the USA?
120 V120\text{ V}120 V alternating current (a.c.) at 60 Hz60\text{ Hz}60 Hz
120 V120\text{ V}120 V alternating current (a.c.) at 50 Hz50\text{ Hz}50 Hz
120 V120\text{ V}120 V direct current (d.c.) at 60 Hz60\text{ Hz}60 Hz
120 V120\text{ V}120 V direct current (d.c.) at 50 Hz50\text{ Hz}50 Hz
39 exam-style questions on OCR GCSE Physics Powering Earth. Each one has a worked solution and a mark scheme showing where the marks go.