In a downtown office building you notice each of the four sections of a rotating door has a mass of 85 kg. What is the width of each section of the door if a force of 52 N applied to the outer edge of a section produces an angular acceleration of 0.480 rad/s2

Suppose that a mass of 2 kg is attached a spring whose spring constant is 50. the system is damped such that b = 12 . the mass is set in motion with an initial velocity of -8 m/s at a position 0 meters from equilibrium. set up and solve a differential equation that models this motion. write your solution in the form a cos ( ω t − α ) where α is a positive number. use your solution to fill in the information below: what is the amplitude of the motion? what is the value of ω ? what is the phase shift?