A student traces one curved line around a bar magnet with a compass. The student claims this proves both that the field is uniform and that its strength is greatest on this line. Which assessment is correct?
Neither claim follows: direction changes along the curve, and the compass does not measure strength.
Only greatest strength follows: direction changes along the curve, but the compass measures strength.
Only uniformity follows: the curve gives constant direction, but the compass does not measure strength.
Both claims follow: the curve gives constant direction, and the compass measures the greatest strength.
70 exam-style questions on Edexcel GCSE Physics 12.1 Magnets and magnetic fields, covering 12.1.1 Magnetic poles, 12.1.2 Magnetic materials; permanent and induced magnets, 12.1.3 Magnetic fields, and 12.1.4 Plotting compasses and the Earth's magnetic field. Each one has a worked solution and a mark scheme showing where the marks go.