×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

TWICE AS HOT

TWICE AS HOT

TWICE AS HOT

(OP)
Time and time again I hear on radio and TV phrases such as “twice as hot”. I even read it in books which should know better.

Often the topic is the weather – it’s 10 degrees in Newcastle but twice as hot in London”. Meaning what exactly? 20 degrees?

But if Newcastle is 10 Celsius, it’s 50 Fahrenheit. Is London 20 Celsius or 100 Fahrenheit? Quite a difference! And what if Newcastle is at minus 5 C?

I guess you can almost justify the expression if the temperature is on an absolute scale but I don’t see many Kelvins on the morning weather forecast. It doesn’t work with any artificial scale such as the ones used in everyday speak.

So, prizes for the most erudite publication to use such a an expression?

Must stop and turn on the aircon. See if I can halve the temperature in here.

Cheers - John

RE: TWICE AS HOT

Maybe if you use the Kelvin or Rankine scales?

Due to illness, the part of The Tick will be played by... The Tick.
http://www.EsoxRepublic.com

RE: TWICE AS HOT

Dammit John, then it would be twice as cold.

RE: TWICE AS HOT

Haven't we done this one already?

RE: TWICE AS HOT

It would be different again on the Réaumur scale

StephenA

RE: TWICE AS HOT

And what if Anders Celsius had kept his first scale? The one where water freezes at 100 C and boils at 0 C? (Yes, that is how he numbered his original scale). Twice as hot would then be half as cold? Or??

RE: TWICE AS HOT

"And what if Anders Celsius had kept his first scale? The one where water freezes at 100 C and boils at 0 C?  "

Then I would have found it twice as confusing...

RE: TWICE AS HOT

Nearly as bad as those sports people who give 110%.

RE: TWICE AS HOT

I knew a girl named Sherry, her sister Heidi was twice as hot.  Oops, that's yet another scale.

RE: TWICE AS HOT

Actually temperature is one criterion. It is difficult to comparitively quantify hotness eventhough we follow a common temperature scale without considering relative humidity.

There is a cute little program here which tells us the relative temperature of ambience with good remarks. (check under heat index)
http://hvacwebtech.com/misctools2.htm

This program is based on ASHRAE's comfort zone.

In both the cases, (Harrisj's and JDana's) hotness is highly subjective.

Regards,

RE: TWICE AS HOT

speaking of hot
I'm looking for a reference or a 'scale' of perceived temperatures and safe temps for physical contact -
In other words when the old maintenance guy puts his hand on the part and "Darn thing's too hot....better get it rebuilt" I'd like to show them that it is really only 100F or so.

Thanks!

Keep the wheels on the ground
Bob
showshine@aol.com

RE: TWICE AS HOT

Sprintcar

You are looking for ASTM C1055 and C1057

Standard Guide for Heated System Surface Conditions That Produce Contact Burn Injuries

and

Standard Practice for
Determination of Skin Contact Temperature from Heated
Surfaces Using A Mathematical Model and
Thermesthesiometer

RE: TWICE AS HOT

(OP)
Sprintcar:

That's a difficult one. A lot depends on the heat content of the item you're touching, and any insulating layer (a coat of paint can make quite a difference).

There's also the variation of skin thickness (ends of fingers have thick calloused skin) and sensitivity (lips are particularly sensitive!)

So you may be able to pick up a piece of dry wood at 100C but a chunk of steel at 50C may feel excruciatingly hot.

Also, mechanics and chefs have 'asbestos fingers' - they've singed themselves so often that their nerve endings have been frazzled.

For engineering applications, it's difficult to tell the difference between 90C and 110C.

You can now get optical thermometers for not much money which give a direct non-contacting reading - they're pretty good.

Cheers - John

RE: TWICE AS HOT

Speaking of "a lot..."  

The traditional definition of "lot" applied to a parcel of land.  Therefore, "lots" meant many parcels, hence a large quantity.  It follows then, that "a" lot, e.g., "one" lot, is a smaller quantity than "lots;"  but in many cases, "a lot" implies a large or larger quantity than its plural.

TTFN

RE: TWICE AS HOT

(OP)
Doesn't make a lot of sense to me ......

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources