A roller-coaster ride has a circular loop with a radius R = 15 m. What is the minimum velocity of the coaster at the base of the loop so that it is capable of completing the loop without falling? Consider g = 9.80 m/s2.

a.
27.1 m/s


b.
29.2 m/s


c.
31.4 m/s


d.
36.3 m/s