In a downtown office building you notice that each of the four sections of a rotating door has a mass of 90 kg. What is the width of each section of the door if a force of 58 N applied to the outer edge of a section produces an angular acceleration of 0.500 rad/s2?

Answer 1

moment of inertia: 4*1/3 90 (r)^2

torque applied*distance=I*ang accelearation
58*r=I*.5=.5*4*1/3 90 (r)^2
solve for r