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.