Describing Rotational Motion

These flashcards cover key vocabulary related to the concepts of rotational motion, such as radians, angular displacement, and angular velocity.

Radian

A unit of angular measurement equal to the angle subtended at the center of a circle by an arc equal in length to the radius of the circle.

Angular displacement

The angle in radians through which a point or line has been rotated in a specified sense about a specified axis.

Translational motion

Motion that occurs when all points of an object move in the same direction and cover the same distance.

Rotational motion

Motion that occurs when an object spins or turns about a fixed axis, causing different points on the object to move along circular paths of different radii.

Counterclockwise rotation

Rotation in the direction opposite to that of a clock's hands, which is considered positive.

Clockwise rotation

Rotation in the same direction as a clock's hands, which is considered negative.

Angular velocity

The rate of change of angular displacement, measured in radians per second.

Arc length

The distance along a circular arc, which is related to the radius and angular displacement.

Circumference

The distance around a circle, calculated as C = 2oldsymbol{ imes} ext{radius}.

Angular acceleration

The rate of change of angular velocity, measured in radians per second squared.