[问答题]
A turntable of radiu/i ;tozvrma xbq)x4)5 s4cz n, w0* xj 6w0xaa.e1i8to gddvz8x $R_1$ is turned by a circular rubber roller of radius $R_2$ in contact with it at their outer edges. What is the ratio of their angular velocities, $\omega_1$ / $\omega_2$