On Mon, 24 Apr 2017 08:19:28 +0100, Chris Hogg wrote:

On Mon, 24 Apr 2017 01:45:45 GMT, Johnny B Good
wrote:

On Sun, 23 Apr 2017 21:42:59 +0100, Vir Campestris wrote:

On 22/04/2017 22:43, Johnny B Good wrote:
On Sat, 22 Apr 2017 12:13:31 +0100, charles wrote:

In article , Tim
Streater wrote:

One of the laws of thermodynamics IIRC - efficiency is related to
the difference between input and output temps - in degrees K, not
C.

my elementary physics suggests that if you are only refering to a
temperature difference the answer is the same in °K and in °C.°

The main benefit of using deg K instead of Deg C is the complete and
utter absence of negative numbers by which to confuse the
mathematics.
:-)

It's true enough that as far as steam engines are concerned, this is
unlikely to effect calculations involving deg C, but there are other
heat engines designs based on fluids with much lower freezing and
boiling points than zero deg C (the triple point of water to within
an accuracy of one decimal place).

FFS Kelvins aren't degrees.

Well, assuming by "Kelvins" you meant Degrees Kelvin and by "degrees"
you meant degrees Celcius, they are!

Degrees Kelvin is not the approved SI unit. The kelvin is, as is K. So
water freezes at 273.15 kelvin or 273.15 K. Not degrees Kelvin, nor
Kelvins nor even kelvins (which I wrongly used in an earlier post).
http://tinyurl.com/kr3l36f

(SI = Somewhat Inconvenient, but there it is!)

Ah! I now see the point being made by Andy. :-)

I like your definition, "SI = Somewhat Inconvenient"[1]. I've watched
enough episodes of "QI" to know better by now. However, in my defence,
I'm not habitually writing scientific papers where such precision of
terminology is a vital part of not being deemed a bit of a Dickhead by
one's peers so lack the experience required to remain up to date with the
latest fads in SI unit terminology.

I'm now aware of the fact that Kelvins (or, more precisely, Kelvin)
*aren't* degrees. :-)

[1] It occurred to me that the misunderstanding was more to do with
semantics so I think a better definition of SI may be[2] "Semantically
Inconvenient".

[2] Please note the *correct* usage of "may be" in this case. I'm sick of
the sight of "may be" when the *single* word "maybe" was intended (along
with the less common but equally irritating use of "maybe" in place of
the phrase "may be"). Apologies for this mini-rant but it *does* feel
good to get that off my chest. :-)

--
Johnny B Good