Does it hack anybody else off ...

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JStarStar

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... When a supposedly "scientific" teevee show cites the speed of light as "186,000 miles per second," instead of the accurate figure of 186,282?

I mean, that last 282 miles per second does matter -- 282 miles per second is a little more than 1 million MPH.

Excuse me while I shake my fist at the teevee again. Grrrrrrrrr. :bang:
 
I'm Ok with that (so long as they use the term "approximately" or "a little over" as a hedge).
 
You do have to look at context though. The percent error there is 282/18,6282 or 0.15%.
 
What's the context? Are they rounding the number because the details are insignificant for the context? Or are they using the rounded figure in an equation and getting bad results?

I round numbers all the time. Unless someone specifically asks me for minute details, then I assume they don't want to get that far down into the weeds.

Case in point: how many people died in the Holocaust? Everyone says 6 million. But I'm sure that's a rounded number. Does it matter that it was really 6,106,512? (I made that up but you get the point.)
 
... When a supposedly "scientific" teevee show cites the speed of light as "186,000 miles per second," instead of the accurate figure of 186,282?

Nope.

And I'm fine with it when they say that Pi = 3.14

One day is not 24 hours long. One (earth) year is not 365 days.

We approximate/round all the time and I'm fine with that.

If I'm not doing a precise calculation that requires the extra digits, close, is usually close enough.
 
Nope.

And I'm fine with it when they say that Pi = 3.14

One day is not 24 hours long. One (earth) year is not 365 days.

We approximate/round all the time and I'm fine with that.

If I'm not doing a precise calculation that requires the extra digits, close, is usually close enough.

This.

But, I do get a little irritated when folks get the BC/AD order mixed with respect to dates. When dates are presented as "1066 AD" (as in the year of the Battle of Hastings), when the correct style is "AD 1066". It's correct to say "586 BC" (as in the year Jerusalem fell to the Babylonians) where the year is given first. Not a big deal, but mildly irritatiing when I hear it from the "educated" elites.

Greg
 
Adding to what John said:

186000 / 186282 = 0.99849
23.934 / 24 = 0.99725

So, stating that the speed of light is 186000 miles per second is more accurate than saying that a day is 24 hours. :)

-- Roger
 
This happens all the time with computer numbers as well... Example RAM
You call it 16gb ram, but it is really 16,384mb but whatever. :p

We are all lazy and round everything...
 
I don't know of any scientific TV shows. Unless you count mermaids, megalodon, or VVVthis guyVVV as "scientific".:y:

9148130.jpg
 
This.

But, I do get a little irritated when folks get the BC/AD order mixed with respect to dates. When dates are presented as "1066 AD" (as in the year of the Battle of Hastings), when the correct style is "AD 1066". It's correct to say "586 BC" (as in the year Jerusalem fell to the Babylonians) where the year is given first. Not a big deal, but mildly irritatiing when I hear it from the "educated" elites.

Greg

I hate to break it to you, but "educated elites" don't use BC and AD at all any more. Now it's BCE and CE (Before Common Era. Common Era). Christ is out the window.

Sorry if I just got this thread closed.
 
Turns out the speed of light is pretty much just a local approximation so some sketchiness in stating the speed is okay in my book.

Now, entropy on the other hand...well, don't get me started on entropy.
 
I look at this topic the same way I look at the unfunded obligations of the federal government...what's a few trillion one way or the other really matter? :facepalm:
 
... When a supposedly "scientific" teevee show cites the speed of light as "186,000 miles per second," instead of the accurate figure of 186,282?

Seeing as they are using miles-per-second, I immediately assume they are not being scientific, and therefore don't expect precision.

"three-hundred-million meters-per-second" <- that would irritate me, even if it is a 0.07% error.

Also, 186,000 mi/s is accurate, to a precision of thousands of miles per second. Three significant figures is about enough for most use.
 
However...

186,000 miles per second is a speed that you, theoretically, can achieve.

186,282 miles per second is a speed that is, theoretically, impossible for you to go.
 
It annoys me 68.37% of the time. The rest of the time I don't care.
 
Nope, doesn't bother me. I actually think it is good practice when conveying scientific concepts and terms to broad audiences to leave out some of the minutia that isn't relavent to the overall concept being explained. There is always at least one more level of detail that even the world's most learned person on a subject will not know.

Not using metric hurts me as a scientist, but again to effectively communicate to a broad group you have to make allowances for what best conveys the concept, not your feelings on what is the most "correct" way to convey the material. The only place I can't stand these approximations is with the difference between weight and mass.
 
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This.

But, I do get a little irritated when folks get the BC/AD order mixed with respect to dates. When dates are presented as "1066 AD" (as in the year of the Battle of Hastings), when the correct style is "AD 1066". It's correct to say "586 BC" (as in the year Jerusalem fell to the Babylonians) where the year is given first. Not a big deal, but mildly irritatiing when I hear it from the "educated" elites.

Greg

I find this funny. One of those things that just does not matter- who cars of the ad comes before or after if everyone knows what is
meant by it?
 
[video=dailymotion;x2ml4wc]https://www.dailymotion.com/video/x2ml4wc_stephen-hawking-sings-monty-python-galaxy-song-music-video_fun[/video]
 
... When a supposedly "scientific" teevee show cites the speed of light as "186,000 miles per second," instead of the accurate figure of 186,282?

I mean, that last 282 miles per second does matter -- 282 miles per second is a little more than 1 million MPH.

Excuse me while I shake my fist at the teevee again. Grrrrrrrrr. :bang:
Actually, what angers me even more is when that figure isn't specified as being accurate in a vacuum.

Just kidding about the angry part.

The speed at which light propagates through transparent materials, such as glass or air, is less than c. The ratio between c and the speed v at which light travels in a material is called the refractive index n of the material (n = c / v). For example, for visible light the refractive index of glass is typically around 1.5, meaning that light in glass travels at c / 1.5 &#8776; 200000 km/s; the refractive index of air for visible light is about 1.0003, so the speed of light in air is about 299700 km/s or 90 km/s slower than c.
 
What really frosts my @$$ is when they don&#8217;t seem to know the difference between a solar system and a galaxy.
 
Yeah! Or auto vs. semi-auto!

[video=youtube;rRSk6iLwK_g]https://www.youtube.com/watch?v=rRSk6iLwK_g[/video]
 
Or when George Lucas wrote into the script for Episode 1, the announcer at the pod race said, "I don't care what universe you're from, that's got to hurt".

Really?
 
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