A 0.395-kg blue bead slides on a frictionless, curved wire, starting from rest at point in the figure below, where h = 1.50 m. At point , the blue bead collides elastically with a 0.650-kg green bead at rest. Find the maximum height the green bead rises as it moves up the wire.

Question

A 0.395-kg blue bead slides on a frictionless, curved wire, starting from rest at point  in the figure below, where h = 1.50 m. At point , the blue bead collides elastically with a 0.650-kg green bead at rest. Find the maximum height the green bead rises as it moves up the wire.

Elena · Answer

m1=0.395 kg, h=1.5 m, m2= 0.65 kg, H=?
m1•g•h=m1•v ²/2
v =sqrt(2•g•h)=sqrt(2•9.8•1.5)=5.4 m/s
m1•v = m1•v1+m2•v2
For the case of elastic collision
v2=2 •m1•v/(m1+m2)= =2•0.395•5.4/(0.395+0.65) =2.67 m/s
m2•v2 ²/2= m2•g•H
H= v2 ²/2•g=2.67²/2•9.8=0.36 m