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jfribrg
2009-Dec-22, 05:29 PM
In this (http://news.yahoo.com/s/ap/eu_britain_prince_william) article about Prince William spending a night on the street to raise awareness about homelessness. At the bottom of the article is a reference to the temperature ( -4 C). The conversion to Fahrenheit claims that -4C is the same as 39 F. Looks like someone forgot to include the minus sign when they used their conversion calculator function. The correct number should be 25 F.

Argos
2009-Dec-22, 05:36 PM
Well, ok. [was it necessary? I don´t have to sleep on the street to know how bad it is...]

Fazor
2009-Dec-22, 05:40 PM
In this (http://news.yahoo.com/s/ap/eu_britain_prince_william) article about Prince William spending a night on the street to raise awareness about homelessness.

See my sig line for an easier way to do it. As a bonus, it requires no particular temperature conversions.

hhEb09'1
2009-Dec-22, 06:12 PM
The are a lot of other versions on the web. Some managed to get the conversion right:

http://www.channelnewsasia.com/stories/afp_world/view/1026450/1/.html

Some wisely didn't even bother converting:

http://www.timesonline.co.uk/tol/news/uk/article6965249.ece

And, others, like this Reuters article, probably were afraid and left off the temperature altogether:

http://uk.reuters.com/article/idUKTRE5BL3792009122

But not Yahoo! :)

Glom
2009-Dec-23, 12:32 PM
Instead of freezing his royal hiney off on the cold streets, I'd rather he be rescuing people freezing their hinies off on the cold mountains like he's supposed to.

captain swoop
2009-Dec-23, 01:05 PM
Is he supposed to do that? why?

mike alexander
2009-Dec-23, 02:29 PM
Is he supposed to do that? why?

It's #34 in the Prince of Wales Handbook.

#34: Go rescue the people freezing on the mountain, you stupid git!

hhEb09'1
2009-Dec-23, 03:21 PM
OK, the original article has been changed! Your hard work and diligence has paid off, jfribrg! Now, the conversion from -4 C is to a precise 24.8 F :)

In looking over some of the other articles, I found some interesting background not in the article linked at the OP. First off, they point out that William is in training to be a full time pilot with the Search and Rescue Force, which is what Glom was alluding to I bet. Second, it mentions that the prince's body guards were stationed a discrete distance away--which is reasonable, and I'm sure the additional body heat wasn't enough to detract from the essential experience, but it does make me wonder about this comment in that article, from the prince's companion:
"But there was no shielding from the bitter cold, or the hard concrete floor, or the fear of being accosted by drug dealers, pimps or those out to give homeless people a 'good' kicking," Obakin said.Maybe he didn't know? thought the body guards were pimps? or maybe he got searched a little roughly?

captain swoop
2009-Dec-23, 03:43 PM
Training to be a pilot and even if trained he wouldn't be on duty 24/7, there's not even a guarentee that he will ever fly a 'live' civilian rescue. RN and RAF Search and Rescue helicopters are there for military use, their primary purpose is to do S & R for crashed aircraft and missing aircrew, only a few are ever on duty.

mike alexander
2009-Dec-23, 04:06 PM
And the temperature gained two significant figures!

jfribrg
2009-Dec-23, 05:56 PM
And the temperature gained two significant figures!

You beat me to it. Even rounding to 25 F is wrong. I guess it would be a little distracting for them to say "somewhere between 24 and 26 degrees F".

Glom
2009-Dec-23, 06:18 PM
Training to be a pilot and even if trained he wouldn't be on duty 24/7, there's not even a guarentee that he will ever fly a 'live' civilian rescue. RN and RAF Search and Rescue helicopters are there for military use, their primary purpose is to do S & R for crashed aircraft and missing aircrew, only a few are ever on duty.

I think one of my friends helped out in a live civilian rescue in the Cairngorms? Or was that a story I heard on TV?

SeanF
2009-Dec-23, 07:41 PM
You beat me to it. Even rounding to 25 F is wrong. I guess it would be a little distracting for them to say "somewhere between 24 and 26 degrees F".
Why would rounding to 25F be wrong?

mike alexander
2009-Dec-23, 08:22 PM
Why would rounding to 25F be wrong?

It's one of those problem you run across when converting between different systems.

in significant figures, unless otherwise stated writing 4C implies an uncertainty of + 1 deg in the value. In Fahrenheit that would be closer to 2deg, so 24-26 is more correct.

But even as a chemist I'm fine with 25 for casual reporting. It's the 24.8 that means someone put the value in some conversion algorithm and just copied the answer, which implies an uncertainty of 0.1 deg F.

captain swoop
2009-Dec-23, 09:19 PM
I think one of my friends helped out in a live civilian rescue in the Cairngorms? Or was that a story I heard on TV?

Yes RAF and RN teams do civilian rescue but it's not their primary role.

hhEb09'1
2009-Dec-24, 02:03 AM
in significant figures, unless otherwise stated writing 4C implies an uncertainty of + 1 deg in the value. In Fahrenheit that would be closer to 2deg, so 24-26 is more correct. Plus or minus one degree C is about plus or minus two degree F, but I would think 4C implies plus or minus 0.5 degree. So, yeah 24-26 F.

It's the same old problem with good old body temp: 98.6F, otherwise known as 37C. Which is why I highlighted it earlier :)

SeanF
2009-Dec-24, 03:00 AM
Plus or minus one degree C is about plus or minus two degree F, but I would think 4C implies plus or minus 0.5 degree. So, yeah 24-26 F.
But doesn't 24-26 imply 24±.5 - 26±.5? :)

I guess this means, though, that "3 feet (36 inches)" would be incorrect, that it should be "3 feet (30-42 inches)" or something.

Significant digits ain't what I thought they were.

jfribrg
2009-Dec-24, 05:03 PM
I'm just thinking about this and it occurred to me that if the original fahrenheit scale had established the freezing point of water at 0 instead of 32, then -4C would be -7F with one significant digit. This is accurate within a degree. If we scale it by 32, we get 25 and still accurate to within a degree, but now we have 2 significant digits. I guess that's why it's better to do the interval arithmetic than rely on significant digits.