## 0567: "Urgent Mission"

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lingomaniac88
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### 0567: "Urgent Mission"

Alt-text: Sure, we could stop dictators and pandemics, but we could also make the signs on every damn diagram make sense.

Yep, we must have our priorities in order...
"It is common sense to take a method and try it. If it fails, admit it frankly and try another. But above all, try something."
-- Franklin D. Roosevelt

rwald
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### Re: "Urgent Mission" Discussion

And while you're at it, you should use your time machine to ensure that pi is defined as the ratio of a circle's circumference to its radius, not its diameter.

icenine
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### Re: "Urgent Mission" Discussion

Ah, our teacher had to explain this confusion in physics class yesterday. Cue the "Why couldn't they just get it right?!"s.

sillybear25
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### Re: "Urgent Mission" Discussion

Fucking "conventional current"

Never did know why we never changed it around once we figured out. Now everyone studying electronics has to know yet another useless tidbit: that conventional current is backwards. Why not just drop it and draw the actual current?
This space intentionally left blank.

TheHand
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### Re: "Urgent Mission" Discussion

Ah, historical figures! Somehow they warm the cockles of my heart.

limerick
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### Re: "Urgent Mission" Discussion

MY GOD, IT'S SO RELEVANT TO MY PHYSICS CLASS RIGHT NOW

Curse you conventional current! Making things very, very confusing ...

10nitro
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### Re: "Urgent Mission" Discussion

Why not do both?, time isn't going anywhere.

or is it?
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rwald
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### Re: "Urgent Mission" Discussion

10nitro wrote:Why not do both?, time isn't going anywhere.

or is it?

Sure, there's a whole list of things one ought to do with a time machine. For example, no trip would be complete without teaching Zeno calculus.

JustMe
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### Re: "Urgent Mission" Discussion

Although this is probably the best use of a time machine ever, the backwards convention is actually helpful. Learning everything we think we know is backwards is actually good preparation for what they like to call "real life."
Especially when you have to deal with a bureaucracy.
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Yggdrasil
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### Re: "Urgent Mission" Discussion

He's just jealous that he's not made of antimatter.

TheHand
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### Re: "Urgent Mission" Discussion

10nitro wrote:Why not do both?, time isn't going anywhere.

or is it?

It's not that it's going anywhere, it's that there is only so much of it.

Gava
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### Re: "Urgent Mission" Discussion

rwald wrote:And while you're at it, you should use your time machine to ensure that pi is defined as the ratio of a circle's circumference to its radius, not its diameter.

No way, that would add a constant to the circle`s area formula...

On the other hand we could make hours, minutes and seconds decimal instead of well you know... (who the hell decided that and what was he thinking...)
we could change the meter so that the speed of light would be a round number then...
prevent the lack of use of metric system in the US....
so many things are just wrong...

EDIT: There where 9 new posts between me deciding to write this and actually posting it. XKCD is growing...fast...
Last edited by Gava on Fri Apr 10, 2009 4:21 am UTC, edited 1 time in total.

WK1
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### Re: "Urgent Mission" Discussion

TheHand wrote:
10nitro wrote:Why not do both?, time isn't going anywhere.

or is it?

It's not that it's going anywhere, it's that there is only so much of it.

If time weren't going anywhere, then a moment would be enough for everybody. Problem is, time is rapidly disappearing, and so we each will eventually have none.

Mavrisa
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### Re: "Urgent Mission" Discussion

If you went back in time to change something, then returned and went back in time to before you went back to change that thing, would it still be changed? I don't like the concept of timetravel. It does terrible things to the cockles of my heart.
"I think nature's imagination is so much greater than man's, she's never gonna let us relax."

Gava
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### Re: "Urgent Mission" Discussion

Mavrisa wrote:If you went back in time to change something, then returned and went back in time to before you went back to change that thing, would it still be changed? I don't like the concept of timetravel. It does terrible things to the cockles of my heart.

Einstein said we couldn't do it (or at least that was what I got from my "modern fisics" course).
I hate Einstein for that...

epsalon
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### Re: "Urgent Mission" Discussion

He should have tried to bribe him with a \$100 bill!

rwald
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### Re: "Urgent Mission" Discussion

Gava wrote:
Mavrisa wrote:If you went back in time to change something, then returned and went back in time to before you went back to change that thing, would it still be changed? I don't like the concept of timetravel. It does terrible things to the cockles of my heart.

Einstein said we couldn't do it (or at least that was what I got from my "modern fisics" course).
I hate Einstein for that...

IIRC, there are still closed timelike curves in relativity, it's just that creating them is very difficult, and there's no sense in which you "change" history; your changes always happened, so you can't change anything you remember having happened different. That's why it's very important when traveling through time to not bring a video camera: if you know that you screwed up, you have no choice but to go back and screw up again.

athelas
A Sophisticated Plagiarism Engine
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### Re: "Urgent Mission" Discussion

You know, if I were to talk to Franklin, I'd probably first talk to him about clearing up the punctuation on the Second Amendment.

seanfalloy
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### Re: "Urgent Mission" Discussion

It would be great if conventional current was the same as current flow but really the definitions we have now work just fine. Every thing that is quantitative must have a definition given to it. If the standard direction of current flow was changed everything would be backward (right-hand rule would be left-hand rule, PNP Transistors would turn on with a positive voltage at the base and NPN would be the other way.) What we have works.
On the other hand Time travel mind fucks are sweet and if I have learned anything from school its that "everything you know is wrong"
--Rumor has it that if you play Microsoft CDs backwards you will hear Satanic messages. Worse still, is that if you play them forwards they will install Windows.

Ghona
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### Re: "Urgent Mission" Discussion

Gava wrote:we could change the meter so that the speed of light would be a round number then...
prevent the lack of use of metric system in the US....

Just change the foot so the speed of light is exactly 10^9 feet/second.
If you're taking me too seriously, you probably are making a mistake.

Gava
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### Re: "Urgent Mission" Discussion

Ghona wrote:Just change the foot so the speed of light is exactly 10^9 feet/second.

sorry, I'm from Argentina and we use metric. I will never understand how much a foot measures... besides i said i would first change the length of a second, so the speed of light would be totally different anyway.

XKCD wrote:We were going to use the time machine to prevent the robot apocalypse, but the guy who built it was an electrical engineer.

Why do you think they were going to kill us all in the first place? I would murder my creator too if I realiced he maintained such a convention.

EDIT: typos (I'm sure there are lots left...)
Last edited by Gava on Fri Apr 10, 2009 4:54 am UTC, edited 1 time in total.

pltnmvenus
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### Re: "Urgent Mission" Discussion

I completely agree with this.

...I have nothing more to say.

'; DROP DATABASE;--
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### Re: "Urgent Mission" Discussion

Nominated for best use of time machine ever.
sillybear25 wrote:Fucking "conventional current"

Never did know why we never changed it around once we figured out. Now everyone studying electronics has to know yet another useless tidbit: that conventional current is backwards. Why not just drop it and draw the actual current?
Hell no. Then you'd look at a diagram and not know whether it's written using the old backward convention or the new proper one. Best just to live with it.

Anyway it can make sense if you just change your perspective. Electricity flows from - to +, thus the - indicates this is the side it's being removed - subtracted - from. Or, electricity flows from + to - (BTW, according to Wikipedia this is the correct statement), thus the + indicates this is the side that's a source (i.e. has a positive amount).
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faunablues
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### Re: "Urgent Mission" Discussion

The proton and electron signs should also be switched. Always bothered me.

Delass
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### Re: "Urgent Mission" Discussion

I never liked that neutron is no charge, and electron is negative. I know neutral, neutron, makes sense. But n is also for negative. Why electron for negative? shrug.

seanfalloy
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### Re: "Urgent Mission" Discussion

Delass wrote:I never liked that neutron is no charge, and electron is negative. I know neutral, neutron, makes sense. But n is also for negative. Why electron for negative? shrug.

Why use "C" for the speed of light. Why use q for charge and Q for reactive Power, I for current, π for 3.14159. They are all just "Names" and names can be anything
--Rumor has it that if you play Microsoft CDs backwards you will hear Satanic messages. Worse still, is that if you play them forwards they will install Windows.

imMAW
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### Re: "Urgent Mission" Discussion

Good comic, I like it.
He should also make sure there's only one definition of ton, that's kind of annoying.

Chuff
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### Re: "Urgent Mission" Discussion

seanfalloy wrote:
Delass wrote:I never liked that neutron is no charge, and electron is negative. I know neutral, neutron, makes sense. But n is also for negative. Why electron for negative? shrug.

Why use "C" for the speed of light. Why use q for charge and Q for reactive Power, I for current, π for 3.14159. They are all just "Names" and names can be anything

C is for cookie. Clearly, cookies and light have some secret connection that we don't know about.
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SciBoy
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### Re: "Urgent Mission" Discussion

There are definitely better uses for a time machine. Like going back and getting Fahrenheit to use some useful references for his damned temperature scale. WTF, using your wife's body temperature for reference?! Also using a completely arbitrary mixture of water, ice and ammonium chloride as the zero point!? You do realize that it's only you and Belize who are still measuring temperature in Fahrenheits. Why not measure it in Nintendo Wii-points or Walt Disneys?

hotaru
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### Re: "Urgent Mission" Discussion

athelas wrote:You know, if I were to talk to Franklin, I'd probably first talk to him about clearing up the punctuation on the Second Amendment.

what, this?
The House voted on September 21, 1789 to accept the changes made by the Senate, but the Amendment as finally entered into the House journal contained the additional words "necessary to":
A well regulated militia being necessary to the security of a free State, the right of the People to keep and bear arms shall not be infringed.[75]

This version was transmitted to the states for ratification.

compare that to this (the wacky ungrammatical misquote preferred by some radical nutjobs, not what the amendment looked like when it was ratified):
A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed.

Code: Select all

`factorial = product . enumFromTo 1isPrime n = factorial (n - 1) `mod` n == n - 1`

aleflamedyud
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### Re: "Urgent Mission" Discussion

Look, there's not going to be a Robot Apocalypse. The Butlerian Jihad will prevent that.
"With kindness comes naïveté. Courage becomes foolhardiness. And dedication has no reward. If you can't accept any of that, you are not fit to be a graduate student."

GrandpaJoe
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### Re: "Urgent Mission" Discussion

ROFLMAO I'm an Electrical Engineering student and this comic pretty sums up my life right now. Well done!

livemansleeping
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### Re: "Urgent Mission" Discussion

I'm a long time reader, first time writer... and when i saw the last comic, i just had to pop in and throw in my two cents.

THANK YOU!!!
there is little which bugs me more in my electrostatics, or electrodynamics classes more than teh fact that by convention, the negatives and posotives are reversed. if this is all you ever use the time machine for, you have my deep, deep thanks.

*note, i'm in no way gonna ask you to stop using the time machine... keep at it! i'm sure theres a number of things you can do that will do nothing but help history...*

i'm still waiting for my future self to appear and hand me plans for a time machine though, still not quite sure why that hasn't happened yet, its annoying, stupid future self.
i am livemansleeping, if you happen to see deadmanwalking, lemme know... >heh.<

pyroman
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### Re: "Urgent Mission" Discussion

As someone who will be taking 5 EE classes next semester (and a token philosophy class... go figure) THANK YOU RANDALL! I mean if they can come up with the metric system to replace the imperial system and revoke pluto's status as a planet why cant they just switch a little sign sigh...
They who can give up essential liberty to obtain a little temporary safety, deserve neither liberty nor safety. - Benjamin Franklin

Snowdream
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### Re: "Urgent Mission" Discussion

I don't think we'll ever have time machines...

I mean, if we did in the future; wouldn't we come back in time to give it to us?
...Unless there are laws in the future, preventing us.
...Or the machine can only go forwards, not backwards.
...Or only backwards my so much (12seconds)
...Or maybe the future hasn't happened yet?
...Or maybe people have gone back in time, and they are living among us.
...Maybe they know we aren't responsible enough to handle the gift.
...where's my tin-foil hat?

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### Re: "Urgent Mission" Discussion

SciBoy wrote:There are definitely better uses for a time machine. Like going back and getting Fahrenheit to use some useful references for his damned temperature scale. WTF, using your wife's body temperature for reference?! Also using a completely arbitrary mixture of water, ice and ammonium chloride as the zero point!? You do realize that it's only you and Belize who are still measuring temperature in Fahrenheits. Why not measure it in Nintendo Wii-points or Walt Disneys?

I just wanted to correct your rant a little bit. First of all, most theories as to how he came up with the numbers are just that: theories. But the one I've read in a few places is that Fahrenheit measured the freezing and boiling points of water, and broke the difference into 180 degrees (360 would have made the spacing too small). Also, it wasn't a completely random mixture for the zero point, it was the coldest solution that he could make. Most think it's just a coincidence that body temperature was approximately 100 degrees.

seanfalloy
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### Re: "Urgent Mission" Discussion

Chuff wrote:
seanfalloy wrote:
Delass wrote:I never liked ...........

Why use "C" for............

C is for cookie. Clearly, cookies and light have some secret connection that we don't know about.

This is defiantly something that must be looked into
--Rumor has it that if you play Microsoft CDs backwards you will hear Satanic messages. Worse still, is that if you play them forwards they will install Windows.

Kailen
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### Re: "Urgent Mission" Discussion

Time is done in the intervals it is becuase the Earth is round. 360 degrees breaks up more easily into multiples of 6 (12, 24, 60), than multiples of 10.

Wouldn't it be easier to, instead of trying to fit time to your definition, go by a base 6, or 12, counting system? Of course, then we run into problems with computers still, with an x^2 base counting system (8 or 16).
* These senseless ramblings brought to you by Insanity™. If you just can't figure the dang thing out, it must be Insanity™.

seanfalloy
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### Re: "Urgent Mission" Discussion

Kailen wrote:Time is done in the intervals it is becuase the Earth is round. 360 degrees breaks up more easily into multiples of 6 (12, 24, 60), than multiples of 10.

Wouldn't it be easier to, instead of trying to fit time to your definition, go by a base 6, or 12, counting system? Of course, then we run into problems with computers still, with an x^2 base counting system (8 or 16).

http://www.infoverse.org/octomatics/octomatics.htm

I'm all for this. I guess it doesn't help that I'm an electrical engineer and I have to deal with decimal to base x^2 every day.
--Rumor has it that if you play Microsoft CDs backwards you will hear Satanic messages. Worse still, is that if you play them forwards they will install Windows.

Sphero09
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### Re: "Urgent Mission" Discussion

pretty good comic as usual...oh and just to clear things up:
GrandpaJoe wrote:ROFLMAO I'm an Electrical Engineering student and this comic pretty sums up my life right now. Well done!

I'm also an Electrical Engineering Student...please don't go thinking that our lives are the result of some historical misinterpretation...obviously GrandpaJoe here has a very poor social life... the average electrical engineering student actually has no life to sum up whatsoever. Oh and I also agree with Chuff, C does stand for cookies.
Kailen wrote:Time is done in the intervals it is becuase the Earth is round. 360 degrees breaks up more easily into multiples of 6 (12, 24, 60), than multiples of 10.

Wouldn't it be easier to, instead of trying to fit time to your definition, go by a base 6, or 12, counting system? Of course, then we run into problems with computers still, with an x^2 base counting system (8 or 16).

This actually bothers me more than the positive/negative issue...Why are the numbers after the decimal point in a second on a base 10 instead of a base 60?..(wait its called a decimal point...i think i just contradicted myself....unless there's a 60ieth-mal point of somekind...help?)