This is the problem: During a certain period of time, the angular position of a swinging door is described by θ = 4.92 + 10.7t + 1.91t2, where θ is in radians and t is in seconds. Determine the angular position, angular speed, and angular acceleration of the door at the following times. then I'm given for part a) t=0s and part b) is t=3.07s I know I have to use the equation for angular position s=r[tex]\theta[/tex] then derive that once for angular velocity ([tex]\omega[/tex]) then take the second derivative for angular acceleration ([tex]\alpha[/tex]). I just don't understand what the values for s and r are and where the come from within this problem. i have that [tex]\theta[/tex](0)=4.92 or .0859rad any help or guidance is much appreciated.