A 5.0-kg ball moving due east at 4.0 m/s collides with a 4.0 kg ball moving due west at 3.0 m/s. Just after
the collision, the 5.0 kg ball has a velocity of 1.2 m/s, due south.
(a) Draw a gure showing the initial and nal con gurations.
(b) What is the velocity of the 4.0 kg ball just after the collision?