In a high-precision optical focusing actuator of a microscope, a coil of wire is suspended within a uniform, radial magnetic field.
When a control current of 16 mA is passed through the coil, a magnetic force of 0.054 N is generated to shift the focusing lens.
The total length of the wire that constitutes the coil is 7.5 m.
Calculate the magnetic flux density of the field surrounding the coil, giving your answer to 2 significant figures.
13 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.