In the figure m1 and m2 (<m1) are joined together by a pulley. When the mass m1 is released from the height h above the floor , it strikes the floor with a speed
2gh(m1−m2m1+m2)
2gh
2m2ghm1+m2
2m1ghm1+m2
Ei=Ef⇒initial energy =Eiand final energy = Ef 0=m2gh−m1gh+12(m1+m2)v2∴v=2gh(m1−m2m1+m2)