Solid Bodies, Such as Mechanical Flywheels, Experience Stress When Rotating

Multiple Choice

Solid bodies, such as mechanical flywheels, experience stress when rotating. The stress s on a flywheel with uniform density d (kg/m³) and radius r (meters) is approximated by where is the rotational speed of the flywheel in radians per second. Estimate the percent increase in the stress if the rotational speed of a uniform flywheel is increased from 3917 to 4067 rad/s. [Note: you should be able to answer the question with the given information: no additional information is necessary.]

A) 8%
B) 3%
C) 0.01%
D) 4%