A 500-Kg Sack of Coal Is Dropped on a 2000-Kg

Multiple Choice

A 500-kg sack of coal is dropped on a 2000-kg railroad flatcar which was initially moving at 3 m/s as shown.After the sack rests on the flatcar, the speed of the flatcar is:

A) 0.6 m/s
B) 1.2 m/s
C) 1.8 m/s
D) 2.4 m/s
E) 3.6 m/s