x=r cos (θ)
y=r sin(θ)
Now we replace the terms in normal motion with their angular motion counterparts.
v = δx/δt
ω = δθ/δt
velocity goes from the change in position over time to angular velocity, the change in angle over time. However, it is defined slightly differently. Velocity is defined with a vector pointing in the same direction as the motion of the object. Angular velocity is defined with a vector pointing perpendicular to the plane of the angular motion. To be more specific, the direction is defined by the cross product of the motion of a point on the edge of the object and the vector from the center of the object to the point.
a = δv/δt
α = δω/δt
Angular acceleration is also defined with a vector perpendicular to the rotational motion of the object. This means that both angular acceleration and angular velocity are defined in the z axis, and for the purposes of basic mechanics, remains stationary.
There are also analogs to the basic equations of motion. Assuming constant angular acceleration we can get:
ωz=ω0z + αzt
θ-θ0=1/2(ω0z+ωz)t
θ=θ0 + ω0zt + 1/2αzt2
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