North Tower Acceleration

[cpwm17]

62. What happens depends on the relative forces on impact

If you drop an object it will accelerate downward due to the force of gravity. But it will also experience an opposing force trying to slow it down: air resistance. If you shoot the object downward fast enough, you can possibly give it an initial velocity above the terminal velocity such that it will decelerate until it reaches its terminal velocity. So here, as in all cases, it depends on the relative forces to determine whether an object accelerates or decelerates.

If you drop a relatively heavy object on a poorly supported small object, the heavy object will accelerate through the impact (depending on their relative masses and their abilities to withstand the impact forces). This is similar to dropped objects accelerating through the impacts with air. If you increase the size of the smaller object above some threshold, there will be a point where the large object will decelerate on impact (but only at the point of impact).

Newton's Third Law is not violated.