Answer:D
Explanation:according to the law of conservation of energy/momentum, when two bodies collides, their total momentum and energy before and after collision are equal. Given that the two bodies move with the same velocities after collision, means that the law has not been violated since momentum = mass x velocity (where mass is constant)
Answer:
B. 2 meters.
Explanation:
To rotate the capstan a certain amount of torque is required, and if each sailor applies a force 
at a distance 
from the center, then for two sailors the total torque will be
;
therefore, for one sailor to apply the same torque it must be that the torque 
he applies must be equal to the torque that the two sailors applied:
which gives
.
and since 
,
which is choice B.
Answer:
the solid particles that settle down at the bottom of the container are known as sediment.
Explanation:
It is a physical change, as only the dimensions changed, not the chemical structure.
