A bead P sliding on a frictionless semi-circular string (A C B) and it is at point S at t =0 and at this instant the horizontal component of its velocity is v . Another bead Q of the same mass as P is ejected from point A at t=0 along the horizontal string A B , with the speed v , friction between the beads and the respective strings may be neglected in both cases. Let t_ P and t_ Q be the respective times taken by b