Question

A hula Hoop (I=1/2MR^2) rolls without sliding along the floor. The ratio of its translational kinetic energy to its rotational kinetic energy (about an axis through its center of mass) is:

A. 1
B. 2
C. 3
D. 1/2

Answer 1

KE*rolling)=1/2 I w^2=1/4 M r^2(v/r)^2=1/4 M v^2
KK(translational)=1/2 M v^2

Looks like translation is twice rolling