An electric bell contains an electromagnet, a springy iron arm carrying a hammer, and a contact screw. When the bell is not ringing, the arm touches the contact screw.
Explain why the hammer strikes the gong over and over while the switch is held closed.
Give the reason why the arm of the bell is made of iron rather than copper.
39 exam-style questions on AQA GCSE Physics 7.2 The motor effect, covering 7.2.1 Electromagnetism, 7.2.2 Fleming's left-hand rule (HT only), 7.2.3 Electric motors (HT only), and 7.2.4 Loudspeakers (HT only). Each one has a worked solution and a mark scheme showing where the marks go.