Rotational Kinematics
SI units & Physics constants
Rotational kinematics investigates lows of motion of objects along circular path without any reference to forces that cause the motion to change

Here (all units see here):
is initial time on time interval in seconds
is final time
is original angular position at time in radians
is final angular position at time 
is angular displacement during time 
is original linear velocity vector at time tangent to trajectory
is final linear velocity vector at time , tangent to trajectory
is total linear acceleration vector, in plane of motion
is normal component of total acceleration vector
is tangential component of total acceleration vector
is radius vector of trajectory, normal to trajectory
is length of path during time 
is angular velocity vector, normal to plane of motion
is angular acceleration vector, normal to plane of motion
General formulas
Angular displacement

Average angular speed on time interval 

Instantaneous angular speed at time 

Original angular speed at time 

Instantaneous angular velocity vector

where is unit vector of z-axis shown in the above diagram
Instantaneous angular acceleration vector

Linear velocity vector is defined by vector product, where is perpendicual to 

Magnitude of linear velocity

Magnitude of normal component of total linear acceleration

Magnitude of tangential component of total linear acceleration

Total linear acceleration vector is defined by vector sum
Magnitude of total linear acceleration

Angle between linear acceleration and linear velocity vectors

Relation between angular acceleration and angular velocity

Kinematic equation for rotation

Uniform rotation



Uniformly accelerated rotation

At the rotation is accelerated
At the rotation is decelerated
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