Monkey and the Hunter 2
The Monkey and hunter is a demonstration of the effects of free fall. A cannon is aimed at a hanging target, and, at the instant the cannon is fired, the target is released from its support. The projectile and the target are entering a free-fall state at exactly the same time. The projectile does hit the target because the only significant force, ignoring drag forces, acting on either the projectile or the target is gravity.
Since gravity affects both objects in exactly the same way, the objects can be thought of as moving in the same reference frame. If we consider the reference frame of constant gravitational acceleration g, the phenomena seem obvious. If we place the same situation in a zero-gravity space, the projectile does not change direction, nor does the target change position- collision is obvious and imminent. A constant, uniform acceleration acting upon the objects in this scenario changes how they move, but does not change how they move relative to each other.