Attraction, in physics and chemistry, a force that draws objects together. There are several forms of attraction. Gravitation holds the planets in their orbits around the sun, and prevents objects on the earth from flying out into space. Cohesion is the attraction between like molecules of a substance, such as the water molecules in a glass of water. Adhesion is the attraction between unlike molecules, such as molecules of glue and those of wood.
Magnetic attraction is the force that draws an iron object to a magnet. Electrostatic attraction draws electrically charged objects toward one another, provided they are oppositely charged. For example, a positively charged glass rod will attract a negatively charged rubber rod.