Definition:Right-Hand Rule
Definition
Axial Vector
Let $\mathbf V$ be an axial vector acting with respect to an axis of rotation $R$.
Consider a right hand with its fingers curled round $R$ so that the fingers are pointed in the direction of rotation of $\mathbf V$ around $R$.
The right-hand rule is the convention that the direction of $\mathbf V$ is the direction in which the thumb is pointing:
Cartesian 3-Space
A Cartesian $3$-Space is defined as being right-handed if it has the following property:
Let a right hand be placed such that:
- the thumb and index finger are at right-angles to each other
- the $3$rd finger is at right-angles to the thumb and index finger, upwards from the palm
- the thumb points along the $x$-axis in the positive direction
- the index finger points along the $y$-axis in the positive direction.
Then the $3$rd finger is pointed along the $z$-axis in the positive direction.
Vector Cross Product
Let a right hand be placed such that:
- the $3$rd finger is at right-angles to both the thumb and index finger, upwards from the palm
- the thumb points along the direction of $\mathbf a$
- the index finger points along the direction of $\mathbf b$.
Then the $3$rd finger is pointed along the direction of $\mathbf a \times \mathbf b$.
Also known as
The right-hand rule can also be seen rendered unhyphenated: right hand rule.