A sandbag is motionless in outer space. A second sandbag with 3 times the mass moving at 12 m/s collides with it and they both stick together and move at a speed of
A) 3 m/s.
B) 4 m/s.
C) 6 m/s.
D) 8 m/s.
E) none of the above
Question 2
A rock is thrown upward with a speed of 15 m/s on the surface of planet X where the acceleration of objects in free fall is 2.5 m/s2 and there is no atmosphere. How long does it take for the rock to return to where it was thrown?
A) 6.0 s
B) 8.0 s
C) 10 s
D) 12 s