Quadrupole

Definitions

1. A distribution of either electric charge or magnetization equivalent to two dipoles that point in opposite directions.
2. A magnet with two north poles and two south poles, used to focus a beam of particles.

Equivalents

Examples

“Consider⟳ a linear quadrupole consisting of a point⟳ charge of strength 2q at the origin and point⟳ charges of strength —q at (0, 0, a) and (0, 0, —a).”

CEFR level