
Round manhole covers, or if Feynman applied for a job at Microsoft - swombat
http://www.sellsbrothers.com/fun/msiview/#Feynman
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sho
One would actually think round manhole covers have several disadvantages to
offset their one purported strength. For example, it would be more difficult
to attach a hinge or locking mechanism. Also, the grip hole would not be
guaranteed to be in the same alignment every time - if you were using a
machine to raise the cover, you might have to manouevre the machine into
incovenient angles to properly access the grip, according to the whim of the
previous team who replaced the cover. With a square lid, the alignment could
be standardised to the most convenient position for machine access. Also,
assuming the bars in the ladder are straight, which AFAIK they always are,
placing a ladder in a round hole wastes space.

Feynmann's answer about the cylinder being the strongest structure against
compression is true but one wouldn't expect this to be a critical factor at
typical street-access depths. Maybe if you were going down 50m or more, but
even so, dirt is hardly as effective at exerting pressure as a free-to-move
liquid.

~~~
something
>Also, the grip hole would not be guaranteed to be in the same alignment every
time

it is if it's in the center.

~~~
biotech
It is easier to replace a circular cover, since you don't have to worry about
it's orientation. I suspect that this is the main reason to use a circular
manhole cover over some other shape.

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ilitirit
I was asked this once during an interview. After I gave several lengthy
possible explanations, the interviewer was basically speechless.

The previous question was much more interesting. I was asked to estimate the
number of piano tuners there were in my city. I got it right, and it turns out
it was one of the the class Fermi questions

[http://mathforum.org/workshops/sum96/interdisc/classicfermi....](http://mathforum.org/workshops/sum96/interdisc/classicfermi.html)

Still, I'm not really a fan of these types of questions. Chances are any
curious person who spends a lot of time on the net would have come across them
some time or another.

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DavidSJ
That doesn't sound anything like Feynman.

~~~
joe_the_user
I _have_ seen man hole covers that _were_ in the shape of other curves of
constant width!! as in the rotary engine shape he describes. Reminds me of the
convex solids class I took at UCLA years ago.

Boy, I always wanted to say that! If only _I_ could pull one of those
interviews.

~~~
Luc
Where did you see those manhole covers? Its seems a bit over-the-top to
manufacture a manhole cover in a weird shape when round or rectangular will
do.

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joshwa
blogspam: original is here:

<http://www.sellsbrothers.com/fun/msiview/#Feynman>

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twopoint718
This reminds me about the story where Feynman is being interviewed by a
psychologist. He answers each question in a way that is both perfectly
reasonable yet would cause the psychologist to become increasingly concerned.

~~~
quantumhobbit
That story was in "Surely you are Joking Mr. Feynman".

~~~
twopoint718
Thanks. I was looking for a "search in book"-type link but couldn't find it.
There are some excerpts on e2 that I found, but not of the passage that I was
thinking of.

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endtime
For what it's worth, I'm interning at Microsoft this summer, and none of my
interviewers (6 or so) asked questions like this. Most of the questions had to
do with arrays of integers, with one linked list question and 1-2 C string
questions.

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johnbender
The only thing worse than this is the trivia questions:

Q: "When using function x does it pull from the thread pool or create a new
thread"

A: Don't care, will google

~~~
cperciva
This isn't trivia. Creating a new thread is expensive; so understanding the
difference can make a huge difference in performance.

Saying "I can google this if I need to" is a cop-out: Yes, you can google if
_if you realize that it matters_ , but if you don't know the answer you're
probably not going to realize that it matters.

~~~
eli
I see what you're saying, but in practice I see no correlation between people
with great recall of arcane functions and syntax and _good developers_.

And the question wasn't, "What's the difference between pulling a thread from
the pool and spinning up a new one?" That's a pretty good question, if you're
going to be doing programming with threads.

~~~
tjr
I don't have any meaningful statistics on this myself, but I always found this
passage from The Jargon File interesting:

 _Another trait is probably even more important: the ability to mentally
absorb, retain, and reference large amounts of ‘meaningless’ detail, trusting
to later experience to give it context and meaning. A person of merely average
analytical intelligence who has this trait can become an effective hacker, but
a creative genius who lacks it will swiftly find himself outdistanced by
people who routinely upload the contents of thick reference manuals into their
brains._

~~~
Retric
The cost of someone trying to upload huge quantities of trivia is a failure to
update when systems change. Consider the cost of creating and maintaining high
quality comments vs readable code.

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anamax
I suspect that Feynman wouldn't have limited himself to two dimensions and
would have noted what the presence of the lip means.

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kul
Feynman would have more fun with this question.

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zandorg
And there's a subtle joke at the end - that he's given a MARKETING position
rather than a programming one!

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mynameishere
This was the test page when they turned the internet on for the first time.

~~~
tptacek
You are my new hero.

~~~
mynameishere
Actually, that joke is extremely old too.

~~~
tptacek
I searched for it and didn't find it. But, OK. You're not my hero anymore.

(wow, tough room).

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farout
he definitely would be a microserf then

