A quick jerk on a sheet of paper beneath a box of cereal doesn't topple the box, which best illustrates that
A) the box has no acceleration.
B) there is an action-reaction pair of forces.
C) gravity tends to hold the box secure.
D) the box has inertia.
Question 2
A moving van with a stone lightly glued to the midpoint of its ceiling smoothly moves at constant velocity. When the glue gives way, the stone falls and hits the floor
A) ahead of the midpoint of the ceiling.
B) exactly below the midpoint of the ceiling.
C) behind the midpoint of the ceiling.
D) none of the above