Posted by Sarah on .
object A of mass 3g with a velocity of 12cm/s to the east, collides with stationary object B. After collision, object A rebounds with a velocity of 10cm/s to the west and object B has a velocity of 1.5cm/s to the east. Calculate the mass of obeject B

Physics 
Elena,
m1 =3 g, v1 =12 cm/s, m2=?, v2 = 0,
u1 = 10cm/s, u2 =1.5 cm.
u1 =(m1m2) •v1/(m1+m2),
u2 = 2•m1•v1/(m1+m2),
u1/u2 = (m1m2) •v1/2•m1•v1.
(10)/1.5 = (3 –m2) •12/2•3•12.
Solving for m2 we obtain
m2 =43 g.