A uniform, solid disk with mass ( m ) and radius ( r ) is pivoted about a horizontal axis through its center. A small object of the same mass ( m ) is glued to the rim of the disk. If the disk is released from rest with the small object at the end of a horizontal radius, find the angular speed when the small object is directly below. The force is exerted by the pivot at this time?
a. ( √2g )
b. ( √2g/3 )
c. ( √3g/2 )
d. ( √3g )