2022 · Q4
Which one of the following statements is not correct?
General KnowledgePhysics
- AAn electric motor converts electrical energy into mechanical energy
- BAn electric generator works on the priniciple of electromagnetic induction
- CThe magnetic field at the centre of a long circular coil carrying current will be parallel straight lines
- DA wire with a green insulation is usually the live wire of an electric supply
Explanation
An electric motor converts electrical energy into mechanical energy, and a generator works on electromagnetic induction — both statements are correct. The field at the centre of a long circular coil (solenoid) is uniform, with parallel straight field lines. However, the green-insulated wire is the EARTH wire; the live wire is usually red or brown. So statement D is the one that is not correct.