Because of uniform angular acceleration, we can use equation of motion in rotation
α =
=
= - 200 π
rad∕m2 KEY CONCEPTS Angular acceleration
In the study of linear motion, we found that the simplest form of accelerated motion to analyze is motion under constant linear acceleration. Likewise, for rotational motion about a fixed axis, the simplest accelerated motion to analyze is motion under constant angular acceleration
Kinematical expressions for rotational motion under constant angular acceleration are of the same form as those for linear motion under constant linear acceleration. We shall not derive them here, but simply, write them from the corresponding linear equations, substituting equivalent angular quantities for the linear ones. Table below displays both sets of equations. For simplicity , we let
x0 = 0 and
θ0 = 0 in these equations. The expressions are valid for both rigid - body rotational and particle motion about a fixed axis.
Equation of motion for constant linear and for constant angular acceleration