Two stones of masses `m and 2 m` are whirled in horizontal circles, the heavier one in a radius `r/2` and the lighter one in a radius `r`. The tangential speed of lighter stone is `n` times that of the value of heavier stone, when they experience same centripetal forces. The value of `n` is
Options:
(a) 2
(b) 3
(c) 4
(d) 1