Angular displacement

Angular displacement
The angle of rotation from the black ray to the green segment is 60°, from the black ray to the blue segment is 210°, and from the green to the blue segment is 210° − 60° = 150°. A complete rotation about the center point is equal to 1 tr, 360°, or 2π radians.
Other names	rotational displacement, angle of rotation
Common symbols	θ, ϑ, φ
SI unit	radian, degree, turn, etc. (any angular unit)
In SI base units	radian (rad)

Classical mechanics
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${\textbf {F}}={\frac {d\mathbf {p} }{dt}}$ Second law of motion
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Core topics Damping Displacement Equations of motion Euler's laws of motion Fictitious force Friction Harmonic oscillator Inertial / Non-inertial reference frame Motion (linear) Newton's law of universal gravitation Newton's laws of motion Relative velocity Rigid body dynamics Euler's equations Simple harmonic motion Vibration
Rotation Circular motion Rotating reference frame Centripetal force Centrifugal force reactive Coriolis force Pendulum Tangential speed Rotational frequency Angular acceleration / displacement / frequency / velocity
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The angular displacement (symbol θ, ϑ, or φ) – also called angle of rotation, rotational displacement, or rotary displacement – of a physical body is the angle (with the unit radian, degree, turn, etc.) through which the body has rotated (revolved or spun) around a centre or axis of rotation. Angular displacement may be signed, indicating the direction of rotation (e.g., clockwise verses counterclockwise); it may also be greater (in absolute value) than a full turn if the rotation was.