As there is no external force on M_(S)+M_(C) system, in horizontal direction, do, momenfum in horizontal disection remains conserned.P_(i)= in'tial momentum of system =M_(S)V_(si)+M_(c)V_(Ci)P_(f)= final momentum (ie-Just af fer collison) =(M_(s)+M_(c))v_(f)from contreination of moment P_(i)=P_(f)on, M_(s)V_(si)+M_(c)V_(c_(i))=(M_(s)+M_(c))V_(f)a. M_(s)r_(si)+0=(M_(s)+m_(c))v_(f)=>(r_(si))/(r_(f))=(M_(s)+M_(c))/(m_(c))on, quad(M ... See the full answer