Answer to skunk's question

[Bartman10]

If it's 0 degrees today, and it's going to be twice as cold tomorrow, how cold will it be?

Do you mean half as hot? Temperature is measured in degrees of heat. Do you mean degrees C or degrees F? Because the final number will be quite different:

In degrees C half of zero is -136.575 degrees C
In degrees F half of zero is -213.835 Degrees F

Most of you will think whatever but I make it my job to inform people about temperature.

Temperature is a measure of molecular agitation. In gasses it is expressed through the pressure of the gas. In solids it is expressed in a variety of ways, including the radiation of electromagnetic rays and in the voltage change across a piece of wire, or the bandwidth of electrical noise generated in a piece of wire.

The temperature scale that is most widely used is the ITS-90 scale which is actually based on the freezing points of different metals, for example zinc has a defined melting point of 419.527 degrees C, and aluminium has a defined melting point of 660.323 degrees C etc. The ITS-90 scale is not a natural scale, and there are small errors in it. If skunk hadn’t asked about half of zero, then the answer above would have had a slight error due to differences in the ITS-90 and thermodynamic temperature scales. Lucky that 0 is (almost) defined on the both ITS-90 and thermodynamic scales.

Well class today’s take home message is: A thermometer measures its own temperature. If your thermometer is not in thermal equilibrium with its surroundings you will not measure what you think you’re measuring.

To find out more about temperature and temperature measurement email me or check out www.irl.cri.nz/msl

[ZorsT]

since 23degrees is good, it will be minus 23

[Virago]

If it's 0 degrees today, and it's going to be twice as cold tomorrow, how cold will it be?

Okay, "twice as cold" must equal "half as hot".

Absolute zero is approx -273 C from memory, so "half as hot" must be -136.5 C.

There's your answer!

[Bartman10]

Okay, "twice as cold" must equal "half as hot".

Absolute zero is approx -273 C from memory, so "half as hot" must be -136.5 C.

There's your answer!

Striaght to the top of the class.

Something went hideously wrong before I'd finished and the post got posted prematurely incase you're wondering about the sudden increase in lecture material for today!

[Hitcher]

Talk about over-complicating an answer!

To answer Skunk's question, one needs to know nothing about physics or chemistry. Mathematics will give you the answer you seek.

For example: If it is 0 degrees celsius today when normally it is 14 degrees, if it is to be twice as cold tomorrow, then the temperature will be minus 28 degrees.

However rather than being pedantically literal, Skunk was probably using a couple of figures of speech: one called exaggeration and the other called irony. And, I suspect, the two were entwined in a rhetorical question.

[mini_me]

Striaght to the top of the class.

Something went hideously wrong before I'd finished and the post got posted prematurely incase you're wondering about the sudden increase in lecture material for today!

haha, you had me totally lost for a moment there

[Drew]

I reackon the Hitch man is right, it was rhetorical, and I have gone cross eyed trying to keep up with what you guys said, tahkns ervy umch!

[WINJA]

Talk about over-complicating an answer!

To answer Skunk's question, one needs to know nothing about physics or chemistry. Mathematics will give you the answer you seek.

For example: If it is 0 degrees celsius today when normally it is 14 degrees, if it is to be twice as cold tomorrow, then the temperature will be minus 28 degrees.

However rather than being pedantically literal, Skunk was probably using a couple of figures of speech: one called exaggeration and the other called irony. And, I suspect, the two were entwined in a rhetorical question.

THAT MAKES NO SENSE , WHEN US PROS DO CALCS WE USE ABSOLUTES AND KELVIN

[Bartman10]

Talk about over-complicating an answer!
For example: If it is 0 degrees celsius today when normally it is 14 degrees, if it is to be twice as cold tomorrow, then the temperature will be minus 28 degrees.

Where did you get 14 degrees C from. Whats 14 degrees C got to do with anything? He asked what half of zero was.

I'm confused by your example, twice as cold as what? Maybe you could reword it.

You can add to the Celsius scale but you can't multiply it. Celsius is not a metric scale. It’s meaningless to talk about fractions of the Celsius scale unless you convert to Kelvin first, do your multiplication and go back to Celsius. Half of 14 Celsius is –129.575 Celsius. –28 has got nothing to do with it.

[WINJA]

I reackon the Hitch man is right, it was rhetorical, and I have gone cross eyed trying to keep up with what you guys said, tahkns ervy umch!

ITS NOT THAT HARD -273 DEGC IS ABSOLUTE ZERO OR ZERO KELVIN, ITS AS COLD AS COLD CAN BE , I DONT THINK ITS BEEN COMPLETELY ACHIEVED BUT WE CAN GET CLOSE USING A CASCADE REFRIGERATION SYSTEM USING HELIUM/NITROGEN/CO2/404A OR R502 AND ME TO BUILD IT FOR YOU
EDIT

[Drew]

THAT MAKES NO SENSE , WHEN US PROS DO CALCS WE USE ABSOLUTES AND KELVIN

Yeah, but who the fuck talks like that in the real world? And calculas, is theorised on an ideal invironment, the real world has too many variables to be measured.

[Hitcher]

THAT MAKES NO SENSE , WHEN US PROS DO CALCS WE USE ABSOLUTES AND KELVIN

I'm sorry about that. Lets say then that today's temperature is is 273.15 degrees Kelvin, when normally it is 287.15 degrees. If it was to be twice as cold tomorrow, it would be 245.15 degrees. I hope that makes more sense for you pros.

[Drew]

Where did you get 14 degrees C from. Whats 14 degrees C got to do with anything? He asked what half of zero was.

I'm confused by your example, twice as cold as what? Maybe you could reword it.

You can add to the Celsius scale but you can't multiply it. Celsius is not a metric scale. It’s meaningless to talk about fractions of the Celsius scale unless you convert to Kelvin first, do your multiplication and go back to Celsius. Half of 14 Celsius is –129.575 Celsius. –28 has got nothing to do with it.

Re-read the question, it says how cold will it be. Even in the ice age, the air temperature didn't get to anywhere near -136. So that is obviously not the answer to the question.

[Hitcher]

Where did you get 14 degrees C from. Whats 14 degrees C got to do with anything? He asked what half of zero was.

No, he said that it was zero degrees today and would be twice as cold tomorrow. He was talking about comparative temperature difference.

14 degrees was my presumed average midday ambient temperature for July.

[Hitcher]

Here's another question for you professional scientists:

The Interisland ferry Awatere is lying at anchor in Wellington harbour. It has a rope ladder hanging down one side. The rungs are made of steel. The ladder has rungs spaced at 0.25m intervals. There are 80 rungs on the ladder above the waterline. It is currently low tide in Wellington harbour. The difference between the high and low tides tonight will be 3.28m. How many rungs on the ladder will be exposed at high tide?