Editing Right-hand rule (section)

===A rotating body===
[[File:Right-hand grip rule.svg|thumb|right|Conventional direction of the axis of a rotating body]]

In mathematics, a rotating body is commonly represented by a [[pseudovector]] along the axis of [[rotation around a fixed axis|rotation]]. The length of the vector gives the [[Angular velocity|speed of rotation]] and the direction of the axis gives the direction of rotation according to the right-hand rule: right fingers curled in the direction of rotation and the right thumb pointing in the positive direction of the axis. This allows some simple calculations using the vector cross-product. No part of the body is moving in the direction of the axis arrow. If the thumb is pointing north, [[Earth's rotation|Earth rotates]] according to the right-hand rule ([[retrograde and prograde motion|prograde motion]]). This causes the Sun, Moon, and stars to [[diurnal motion|appear to revolve]] westward according to the left-hand rule.