A sphere a disk and a hoop made of homogeneous materials have the same radius (10 cm) and mass (3kg) They are released from rest at the top of a `30^(@)` incline and roll down without slipping through a vertical distance of 2m. `(g=9.8m//s^(2))`
(a). What are their speeds at the bottom?
(b). findt the friction force `f` each case
(c). if they start together at `t=0`, at what time does each reach the bottom?