Two identical uniform discs roll without slipping on two different surfaces AB and CD (see figure) starting at A and C with linear speeds $$v_1$$ and $$v_2$$, respectively, and always remain in contact with the surfaces. If they reach B and D with the samelinear speed and $$v_1 = 3 m/s$$, the $$v_2$$ in m/s is ($$g = 10 m/s^2$$)