A 1.6-kg ball is attached to the end of a 0.40-m string to form a pendulum. This pendulum is released from rest with the string horizontal. At the lowest point of its swing, when it is moving horizontally, the ball collides with a 0.80-kg block initially at rest on a horizontal frictionless surface. The speed of the block just after the collision is 3.0 m/s. What is the speed of the ball just after the collision?
1) 1.7 m/s
2) 1.1 m/s
3) 1.5 m/s
4) 1.3 m/s
5) 2.1 m/s
Answer: 4