6. Two particles, each of mass m, are connected by a light inextensible string of length 2l. Initially they lie on a smooth horizontal table at points A and B distant l apart. The particle at A is projected across the table with velocity u. Find the speed with which the second particle begins to move if the directions of u is. (a) along AB, mu = (m+m)v v = u/2 But the given answer is u/2 and mu/2. Can anyone explain to me why there are 2 answers? Thanks.