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The Brainteaser Elon Musk Asks New SpaceX Engineers
Nerval's Lobster writes: The latest biography of Elon Musk, by technology journalist Ashlee Vance, provides an in-depth look into how the entrepreneur and tech titan built Tesla Motors and SpaceX from the ground up. For developers and engineers, getting a job at SpaceX is difficult, with a long interviewing/testing process... and for some candidates, there's a rather unique final step: an interview with Musk himself. During that interview, Musk reportedly likes to ask candidates a particular brainteaser: "You're standing on the surface of the Earth. You walk one mile south, one mile west, and one mile north. You end up exactly where you started. Where are you?" If you can answer that riddle successfully, and pass all of SpaceX's other stringent tests, you may have a shot at launching rockets into orbit.
The harder brainteaser they SHOULD ask:
A large, cylindrical object is falling. You want it to land upright, with the correct end down. Which of these strategies do you choose:
a) Attach a parachute to the nose and let basic physics work.
b) Try to balance it atop rocket engines firing from the bottom.
or a treadmill, but you'd have to turn it 90 degrees clockwise twice.
Who ordered that?
You'd only be partially correct.
There are actually multiple solutions:
1.) North Pole (one mile south, one west, and one north brings you back to the north pole)
2.) A ring of points approximately 2 miles just north of the the south pole, such that when you walk one mile south, you're even closer to the pole, then walk one mile west, going completely "around the world", back to where you started your westward travel, and one mile north, bringing you back to your original position.
Or another ring of points closer to the south pole such that you go completely around the world twice, and another ring closer such that you go around the world 3 times....
Apply your own interpretation of the words and grammar in this post.
The north pole and a circle of lat 1 + 1 / (2 * PI) north of the south pole.
Actually the answer is the north pole and a circles of lat 1 + 1 / (2*pi*n) north of the south pole where n=1,2,3,4... etc. plus there is a slight correction because the surface of the earth is not entirely flat and so the circumference of a line of latitude is actually less than 2*pi*s where s is the arc length from the line to the south pole for the distances involved it would probably be negligible compared to surface defects.
The Brainteaser Elon Musk Used To Ask New SpaceX Engineers, Because His Old Question Got Slashdotted.
Thanks jerks!
Left MS Windows for Linux Mint and never looked back!
Vote for Bernie in 2016!
I interviewed with SpaceX for a senior-level software position last year, and was offered the job but turned it down on logistical grounds.
I did indeed have to take the tests mentioned here, and did have to interview with Musk himself as the final step. However, he did not ask me this brain teaser question. In fact, he specifically said he doesn't ask brain teaser questions because they are dumb.
Nor would he likely ask such a well-known and old brain teaser anyway. This seems like one of those things erroneously attributed to "Bill Gates" over the past 20 years because he is famous and smart, and fits people's preconceptions.