[问答题]
A turntable of radiue0mmgg9;j/c+/keu wy s; uqv-.cm;hb y0o ys/hvviu;+, l*yis $R_1$ 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, $\omega_1$ / $\omega_2$