Kinematics (angular motion)
Definition
Formulae
angular velocity
angular displacement
angular acceleration
measure using rad
1 rev = 360 deg = 2pi rad
denoted by theta
It is defined as the angle and the direction through which a body turns
denoted by w
measured using rad/s or rpm
It is the rate of change of angular displacement with respect to time
measured using rad/s^2
denoted by a
It is the rate of change of angular velocity with respect to time
constant angular acceleration
relationship with linear motion
where
r = radius of rotation [m]
s = linear displacement [m]
θ = angular displacement [rad]
v = tangential velocity [m/s]
ω = angular velocity [rad/s]
at = tangential acceleration [m/s2]
α = angular acceleration [rad/s2]
an = normal or centripetal acceleration [m/s2]
motion
Translational
Rotational
Every particle in the rigid body has the same instantaneous velocity.
Every particle in the rigid body has the same angular velocity and travels in circles around a fixed axis.
Rolling
Translational + Rotational = Rolling