Physics
Physics
Problem
A miniature bar magnet produces a magnetic field of at a distance of along its axis. How far from the magnet’s center (along the same axis) must you move so that the field magnitude drops to ? Give your answer to two significant figures.Intuitive explanation
Magnetic field strength from a bar magnet falls off as the inverse cube of distance along the axis—that's the key relationship here. Since you know the field at one distance and want to find where it reaches a different value, you can set up a ratio that cancels the unknown constant and lets you solve for the new distance directly without needing the magnet's moment.
Intuitive explanation
Magnetic field strength from a bar magnet falls off as the inverse cube of distance along the axis—that's the key relationship here. Since you know the field at one distance and want to find where it reaches a different value, you can set up a ratio that cancels the unknown constant and lets you solve for the new distance directly without needing the magnet's moment.