The uniform semicircular bar of radius r = 75 mm and mass m = 3 kg rotates freely about a horizontal axis through the pivot O. The bar is initially held in position 1 against the action of the torsional spring and then suddenly released. Determine the spring stiffness k_T which will give the bar a counterclockwise angular velocity w = 4 rad/s when it reaches position 2, at which the spring is undeformed.

Transcribed Image Text:

-+- A' kT 1 А т 2. |