A Sandbag in Outer Space Moves at 3 M/s When

Multiple Choice

A sandbag in outer space moves at 3 m/s when it collides and sticks to a half-as-massive sandbag initially at rest. Compared with the kinetic energy of the moving sandbag before collision, the kinetic energy of the coupled sandbags after collision is

A) one-third.
B) two-thirds.
C) three-quarters.
D) not enough information