Two identical solid disks, X and Y, rotate together about their central axes with the same constant angular speed. Disk X has twice the radius of disk Y. Which of the following statements correctly compares the linear speed of a point on the rim of disk X (vX) with that of a point on the rim of disk Y (vY)?
a) vX=vY
b) vX=2vY
c) vX=21vY
d) The comparison cannot be made without knowing the masses of the disks.