It’s two o’clock in the morning, and you’re stumped by a hard problem. Your neural network is as paralyzed as Cairo traffic on a Thursday night… Finally, after going on first gear for way too long, it starts to loosen up, only for you to realize that you’ve run out of gas.

Stupid.

How do you make yourself feel a little smarter than the average zoo resident? Well, bring the level of difficulty down. Way down. And no problem is easier than one that you already know the solution to.

This brings us to tonight’s puzzle: The hunter and the monkey. It’s a classic physics puzzle about, what else, a hunter who is trying to shoot, ehem, a monkey on a tree. (Or–for the PETA card-carrying member–a coconut carried by a monkey on a palm tree. Don’t ask why the hunter/gatherer wants the particular coconut that the monkey has, or why they would even want to shoot a coconut in the first place. But I digress.) The monkey drops (the coconut) from the tree in the same instant the hunter fires his shot. The question is (assuming no air resistance) where should the hunter aim? I guess your choices are: above, at, or below the monkey. Oh, and of course we shouldn’t forget the dreadful second part of the question, and why?

I know the answer to this one. (So, I feel better already.) It goes [something] like this:

(Sorry for the tease. If you can’t wait till tomorrow for the answer, look it up.)

The hunter should aim straight at the monkey (coconut), the reason being (from wikipedia):

To answer this question, recall that according to Galileo’s Law, all objects near the Earth’s surface fall with the same constant acceleration, 9.8 meters per second per second (32 feet per second per second), regardless of the object’s weight. Furthermore, horizontal motions and vertical motions are independent: gravity acts only upon an object’s vertical velocity, not upon its velocity in the horizontal direction… The hunter’s dart, therefore, falls with the same acceleration as the monkey.

The article on wikipedia also explains other ways of looking at the problem in terms of reference frame transformations.

Or, if you’d rather see an animation, click on this image.