• Nzall (disco)

    I don't get what the problem with the Frist image is. Isn't 44F about equal to 7C?

  • VinDuv (disco) in reply to Nzall

    Thanks, I was wondering how they got that value. They just blindly converted it. The problem is, it’s not a temperature. It’s a temperature offset. Let’s say the current temperature is 104°F/37°C. This thing is supposed to keep the car at 104 - 44 = 60°F, which is 15°C. So the 44°F offset results in a 37 - 15 = 22°C offset, not 7.

  • JoergNeulist (disco) in reply to Nzall

    In absolute values, yes. But the conversion is affine, not linear (that means 0°C is not equal to 0°F). The ad talks about a CHANGE in temperature, and there 44°F is more like 24°C (the factor is 9/5).

  • Steve_The_Cynic (disco)

    Re: shipping in/to the US. It's a good wheeze, actually.

    If the warehouse / factory / other place they'd ship from isn't in the US, then nobody can have "free shipping in the US because the shipping(1) doesn't happen in the US, just the transport and delivery.

    (1) Where "shipping" refers to the process of giving the package to the courier, of course, rather than the stuff the courier does.

    Of course, what we all think is that "free shipping in the US" means "free shipping to customers who are in the US", but it doesn't necessarily mean that, and when reading advertising, you generally should assign to any ambiguous phrases the meaning that's the least favorable to the customer. God knows, the advertiser will, so you should match that in order to avoid disappointment.

  • Steve_The_Cynic (disco)
    Comment held for moderation.
  • no laughing matter (cs)

    ˙ʇuǝɯɯoɔ ʇsıɹɟ ɟo uoıʇɐʇoɹ pǝʇǝןdɯoɔ

  • Zecc (disco) in reply to Steve_The_Cynic
    Comment held for moderation.
  • Pippo (disco)

    Isn't 104 F equal to 40 C?

  • Eldelshell (disco)
    Comment held for moderation.
  • anonymous (unregistered)

    So, did Thomas try pushing the NO button?

  • warreng (disco)

    A trio of error screens? Is TRWTF my counting?

  • Matt_Westwood (disco) in reply to Zecc

    A difference of 7 degrees Celsius is obviously a difference of 12.5 degrees Fahrenheit. But the stoopid who put the sign together got the concept of an offset (aka delta, or temperature difference) confused with "what is the Fahrenheit measure of the temperature which in Celsius is rendered as 7 degrees above the temperature at which ice melts".

    What surprises me is that so many readers here, like the creator of the sign, don't perceive the subtlety.

  • Matt_Westwood (disco)

    Reminds me of:

    "It was one degree Celsius yesterday, but it's 7 degrees Celsius today. So it's seven times hotter today than it was yesterday."


  • ZPedro (disco)

    This supports my theory that we should cease usage of non absolute zero based temperature units. Long live the Kelvin! Another advantage: no more pesky negative temperatures (the original motivation for Fahrenheit, remember?)! They would be thermodynamicallly impossible!

  • Anonymous (disco) in reply to Matt_Westwood

    My answer is 280.15K / 274.15K = 1.0_21885828925770563560094838592011672442093744300565383913915739558635783330293634871420755061097939084442823271931424402699252234178369505745030093014772934524895130403064016049607878898413277402881634141893124202079153747948203538209009666241108881998905708553711471821995258070399416377895312784971730804304213022068210833485318256428962246945103045777858836403428779865037388291081524712748495349261353273755243479846799197519606055079336129855918292905343789896042312602589823089549516687944555900054714572314426408900237096480029181105234360751413459784789348896589458325734087178551887652744847711107058179828561006748130585445923764362575232536932336312237826007660040124019697246033193507204085354732810505197884369870508845522524165602772204997264271384278679554988145175998540944738281962429327010760532555170527083713295641072405617362757614444647091008571949662593470727703811781871238373153383184388108699616997993799015137698340324639795732263359474740105781506474557723873791719861389750136786430786066022250592741200072952763085901878533649461973372241473645814335217946379719131862119277767645449571402516870326463614809410906438081342330840780594565019150100310049243115082983768010213386832026262994710924676272113806310414006930512493160678460696698887470362939996352361845704906073317526901331387926317709283239102681014043406894036111617727521429874156483676819259529454678095932883457960970271749042494984497537844245850811599489330658398686850264453766186394309684479299653474375341966076965165055626481853000182381907714754696334123654933430603684114535838044865949297829655298194419113623928506292175816159037023527266095203355827101951486412547875250775123107787707459420025533467080065657486777311690680284515776035017326281232901696151741747218675907349990880904614262265183293817253328469815794273208097756702535108517235090279044318803574685391209192048148823636695239832208644902425679372606237461243844610614627028998723326645996717125661134415465985774211198249133685938354915192412912639066204632500455954769286886740835309137333576509210286339595112164873244574138245486047784059821265730439540397592558818165238008389567754878716031369688126937807769469268648550063833667700164143716943279226700711289440087543315703082254240379354368046689768374977202261535655662958234543133321174539485683020244391756337771293087725697610797008936713478022980120372059091738099580521612256064198431515593653109611526536567572496808316614991792814152836038664964435527995622834214845887287981032281597665511581251139886923217216852088272843333941273025715848987780412183111435345613715119460149553164326098850993981397045413095020973919387196790078424220317344519423673171621375159584169250410359292358198066751778223600_ (recurring) times hotter

  • Steve_The_Cynic (disco) in reply to Zecc
    Comment held for moderation.
  • Steve_The_Cynic (disco) in reply to Pippo
    Isn't 104 F equal to 40 C?
    No, 104 farads is not equal to 40 coulombs.
  • cellocgw (disco) in reply to Pippo

    Dunno, but I hear that 25 Dec is the same as 31 Oct //rim-shot

  • Hannes (unregistered)

    completed rerotation of frist comment.

  • Zecc (disco) in reply to Steve_The_Cynic
    Comment held for moderation.
  • Nzall (disco) in reply to Zecc

    I have never worked with Fahrenheit before, so I didn't realize that a temperature difference in Fahrenheit is not always the same. I only work with Celsius, which doesn't have that silly problem. a 7C difference always is the same.

  • aliceif (disco) in reply to Nzall

    You're understanding things wrong. The difference between 0°F and 100 °F is the same as the difference between 100°F and 200°F, just like it is on the Celsius scale. The issue with the sign is that they used the wrong kind of conversion: 44°F is meant to be a temperature difference. A difference of 1°F is the same as a difference of 5/9°C. The correct result should be 24°C. The sign used the conversion for an absolute temperature, though. If it's 44°F outside, that's the same temperature as 7°C. The reason? When converting an absolute temperature, the difference between 0°F and 0°C gets added/substracted in the process. This is of course not necessary when calculating differences.

  • cellocgw (disco) in reply to aliceif

    Thanks, Captainette Obvious

  • aliceif (disco) in reply to cellocgw

    You're welcome! :ship:

  • Fellshard (disco) in reply to Anonymous

    How dare you bring your properly-rooted systems of measurement in here? The nerve, really...

  • Tsaukpaetra (disco) in reply to aliceif

    What happened to your avatar's leg :interrobang: And arms? :vibration_mode:

  • nmclean (disco) in reply to Steve_The_Cynic

    Conjecture: Steve and others have a history of manual calculation and naturally think of C and F in terms of the 5/9 constant, while the rest of us are spoiled by automated converters. I admit my automatic reaction was to type "44f to c" into chrome's address bar and I had a moment of confusion too; then I remembered that zero doesn't mean "nothing" here, but again instead of doing the proper calculation I simply changed that to "88f to c" and noted the difference.

  • antiquarian (disco) in reply to Steve_The_Cynic
    Comment held for moderation.
  • Zainab58 (disco) in reply to VinDuv

    You gotta admit it would be funnier-- and probably more truthful-- if the device only cooled your car by about 12-13°F.

  • Zainab58 (disco) in reply to Nzall

    Thank you for assuring assorted people upthread that you were not trolling us and your initial comment was indeed meant to be taken at face value.

  • Gurth (disco) in reply to Zainab58

    So, it indicates the real amount by which it cools down the car (7° C) and at the same time makes it appear much better than it actually is to most people likely to buy one. Marketing genius, if you ask me!

  • aliceif (disco) in reply to Tsaukpaetra

    They're white. That's why you can't see them on a white background.

  • FrostCat (disco) in reply to aliceif
    They're white. That's why you can't see them on a white background.

    How about that. Looks like you'r still missing a leg, though, unless they're both next to each other and/or crossed.

  • aliceif (disco) in reply to FrostCat

    I guess they are. I'm not an expert on fairies living in boxes in futuristic space land, though.

  • Tsaukpaetra (disco) in reply to aliceif

    We will choose to believe that she is merely flying to perspective right, torso twisted perspective back. ;)

  • FrostCat (disco) in reply to aliceif
    Comment held for moderation.
  • nmclean (disco) in reply to FrostCat

    aliceif.html? You know, you could have just used the browser dev tools to add background:black to the img element.

  • FrostCat (disco) in reply to nmclean
    aliceif.html? You know, you could have just used the browser dev tools to add background:black to the img element.

    Yeah, probably, but I didn't think of it.

    What would YOU have named the file? I already had test.html through another-test-1138.html

  • CoyneTheDup (disco) in reply to Matt_Westwood

    This is even more fun with negative numbers and zero.

    "Yesterday, it was -21 degrees F; today it's 7 degrees. So it's -1/3 hotter than it was yesterday."

    "Yesterday, it was 0 degrees F, today it's 1 degree F. It is infinitely hotter today than yesterday."

    It is amazing how many people encounter problems distinguishing between conversion from the Fahrenheit scale to the Celsius scale, versus conversion of a Fahrenheit interval to a Celsius interval. And, of course, how many people blindly do nonsense stuff like the above.

  • cellocgw (disco) in reply to antiquarian

    Thanks :-) I'll try to remember that if I ever get to play the Schubert. In my case, a wild&crazy youth spent transposing clarinet and sax parts from Bb to Eb and back (a 4th or 5th), Bb to C, A to Bb, and more makes dealing with different clefs a breeze!

  • garaden (disco) in reply to CoyneTheDup

    I had a similar problem when studying power. High-voltage power lines experience less loss than low-voltage ones, but I was having trouble understanding why. It made sense given that power = I^2 * R, but not given power = V^2 / R.

    It took me a while to realize that V was the voltage drop along the line, not the difference between the line and ground. Whoops.

  • Matosawitko (disco)

    AppFresh apparently went stale.

  • nmclean (disco) in reply to FrostCat
    What would YOU have named the file? I already had test.html through another-test-1138.html

    Well, the idea was I wouldn't have created a file in the first place.

  • boomzilla (disco) in reply to Nzall
    I have never worked with Fahrenheit before, so I didn't realize that a temperature difference in Fahrenheit is not always the same. I only work with Celsius, which doesn't have that silly problem. a 7C difference always is the same.



  • FrostCat (disco) in reply to nmclean
    Well, the idea was I wouldn't have created a file in the first place.


  • nmclean (disco) in reply to FrostCat


  • FrostCat (disco) in reply to nmclean

    I made my test in a WTFy manner on purpose.

  • Matt_Westwood (disco) in reply to aliceif

    Now the real WTF here is the people who believe that 44 degrees Fahrenheit is the actual advertised temperature drop and 7 degrees Celsius is the incorrectly-converted temperature calculated from it. A minute or two thinking about the real physics of the situation should be enough for a person to realise how stupid that suggestion is.

  • aliceif (disco) in reply to Matt_Westwood

    What, you don't use those shades to use your car as a fridge during slightly less warm summer days? (I know that 7°C is the actual correct value, which should be ... 12°F?)

  • dkf (disco) in reply to CoyneTheDup
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