A data CD takes 3 [seconds] to reach its operating rotational speed of 5400 [rpm] (revolutions per minute). What is the CD's average acceleration while it is getting up to speed? A) 190 [rad/s²] 1,700 [rad/s²] C) 16,200 [rad/s] D) Don't know B) E) Who uses CD's anymore?

An electric fan is turned off, and its angular velocity decreases uniformly from 450 rev/min to 220 rev/min in a time interval of length 4.50s.  a) Find the angular acceleration α in revolutions per second per second.  b) Find the number of revolutions made by the fan blades during the time that they are slowing down in Part A.  c) How many more seconds are required for the fan to come to rest if the angular acceleration remains constant at the value calculated in Part A?

Number 4 needs answered

9 - A tire with a radius of 0.5 m rotates at a constant speed of 200 rpm. Find the acceleration of a small stone on the outer edge of the tire.    a) 219 m/s^2  B) 312 m/s^2  NS) 102 m/s^2  D) 153 m/s^2  TO) 187 m/s^2

2) A bicycle wheel is rotating at 18 rad/s. The person is pedaling such that the wheel is accelerating at 4 rad/s^2.How much time elapses until the bike rider is moving at 20 m/s? Assume the bicycle has 27 inches diameter wheels. a) 10.1 s b) 9.3 s c) 58.4 s d) 15.4 s e) 28.9 s

The second power of the distance from the inertia axis to an element of area is used to calculate the: a)Area of an object. b)Gravitational potential energy of an object. c)Centroid of an object. d)Second moment of area or moment of inertia of an object.