# Rotation around a fixed axis

Special case of rotational motion.

- Rotation around a fixed axis8 related topics

## Angular velocity

In physics, angular velocity or rotational velocity ('''

In physics, angular velocity or rotational velocity ('''

Orbital angular velocity refers to how fast a point object revolves about a fixed origin, i.e. the time rate of change of its angular position relative to the origin.

## Rigid body

Solid body in which deformation is zero or so small it can be neglected.

Solid body in which deformation is zero or so small it can be neglected.

Two points of a rotating body will have the same instantaneous velocity only if they happen to lie on an axis parallel to the instantaneous axis of rotation.

## Precession

Change in the orientation of the rotational axis of a rotating body.

Change in the orientation of the rotational axis of a rotating body.

In an appropriate reference frame it can be defined as a change in the first Euler angle, whereas the third Euler angle defines the rotation itself.

## Right-hand rule

Common mnemonic for understanding orientation of axes in three-dimensional space.

Common mnemonic for understanding orientation of axes in three-dimensional space.

In mathematics, a rotating body is commonly represented by a pseudovector along the axis of rotation.

## Nutation

Nutation is a rocking, swaying, or nodding motion in the axis of rotation of a largely axially symmetric object, such as a gyroscope, planet, or bullet in flight, or as an intended behaviour of a mechanism.

## Center of mass

Unique point where the weighted relative position of the distributed mass sums to zero.

Unique point where the weighted relative position of the distributed mass sums to zero.

Typically, a human's center of mass is detected with one of two methods: the reaction board method is a static analysis that involves the person lying down on that instrument, and use of their static equilibrium equation to find their center of mass; the segmentation method relies on a mathematical solution based on the physical principle that the summation of the torques of individual body sections, relative to a specified axis, must equal the torque of the whole system that constitutes the body, measured relative to the same axis.

## Centrifugal force

Inertial force that appears to act on all objects when viewed in a rotating frame of reference.

Inertial force that appears to act on all objects when viewed in a rotating frame of reference.

It is directed away from an axis which is parallel to the axis of rotation and passing through the coordinate system's origin.