In Francis Turbine, the speed ratio comes out to be 0.8 under the head of 150 m, If another Francis Turbine has a speed ratio of 0.6 with the same head, then the ratio of tangential velocity of the second turbine to that of first is ________.
1
\(\rm \dfrac{4}{3}\)
2
\(\rm \dfrac{2}{3}\)
3
\(\rm \dfrac{3}{2}\)
4
\(\rm \dfrac{3}{4}\)