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Strange New Physics! Water boils slower in the US

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IRstuff

IRstuff

Aerospace
Jun 3, 2002
44,695
We typically travel with a portable water heater for boiling water to make tea while traveling, because when the hotels have coffee makers, they're typically so imbued with coffee taste that even several pots of clear water still result in a strong coffee smell.

Interestingly, in the last 4 countries we visited, water boils approximately 4 times faster there than at home.


It's the electrical power, of course; all 4 countries we visited use 220VAC, so double the voltage, hence quadruple the power, so approximately 4 times faster boiling.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
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Voltage?

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)
 
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Just make sure it is actually dual voltage / power rated....

It must take an age to boil stuff at 110V...

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
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Back in grade ten, the science teacher was giving us that line, a high resistance generates heat.
I ran the numbers and demonstrated that for a given voltage, The higher the resistance, the less current and therefore the less heat.
He didn't really understand the material that he was presenting by rote, and could not explain the apparent discrepancy.
His only recourse was to hate me.
There may be some unspoken and possibly invalid assumptions in this thread.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!
 
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Clearly didn't understand Power = I^2 R then?

"His only recourse was to hate me." - That's a bit extreme.

BTW what's Grade 10? In the UK we work in years of schooling so Y1 starts at age 5. Is grade the same?

If so that's terrible teaching for pupils who are 14/15 years old.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
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BTW what's Grade 10? In the UK we work in years of schooling so Y1 starts at age 5. Is grade the same?
Click to expand...

Roughly, yes; typically, grade 1 is for 6 yr-olds. and grade 10 would be the sophomore year of American high school

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
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Water heaters are one of the few appliances that may often (but not always) be connected to double rated voltage and not burn out quickly.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!
 
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Is there a real advantage with 220 in using smaller wire, since the current can be half? I know this was the case when automobiles went from 6v to 12v.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik
 
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I think the advantage comes mainly in being able to use higher-powered portable appliances without the flex becoming inconveniently stiff. In a domestic setting, this boils down (you see what I did there) to whether the electric kettle is a practical proposition.

A.
 
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thanks...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik
 
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IRStuff said:
boils approximately 4 times faster
Click to expand...

Don't you mean "boils in approximately 1/4 the time"? Or maybe (1/2)^2 the time.

Anyway, here in Japan the voltage is only 100 V, and yet "denki kettle" (electric kettles) are ubiquitous.

Ours is 1200W.

Technology Connections on electric kettles:
 
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There are electric kettles in the US, as well, but obviously, the boiling time is MUCH SLOOOOWER; you've got enough time to open a box of tea leaves, scoop out the desired amount, place in strainer, and still have time to watch for bubbles. At 220V, you fill the kettle and it's about 30 seconds to a roiling boil.

And yes, 4 times faster, i.e., rate of boil = roiling boiling / time to boil, just like saying Warp 2 is 8 times faster than Warp 1 (TOS).

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
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What is the total KWH for both voltages? Are they the same?

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik
 
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That says you're applying 240V to the same element to which you apply 120V. Anything that will allow you do that is going to be slow at 120V. But if you compare a 1200W 120V unit against a 1200W 240V unit you will find comparable times.

When one this sentence into the German to translate wanted, would one the fact exploit, that the word order and the punctuation already with the German conventions agree.

-- Douglas Hofstadter, Jan 1982
 
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What is the total KWH for both voltages? Are they the same?
Click to expand...

Not for the kettle we're using; obviously, power is quadrupled, roughly, although the heater elements are running somewhat hotter, so slightly higher resistance than at 120V input

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
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Is there a power savings using 240V? If so, then higher voltage might be the future?

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik
 
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Ostensibly, yes; a lower current for a given wattage rating would mean less IR loss, and a higher voltage allows more devices to operate on the existing 15-A wiring in the US, assuming they're power-limited. The existing wiring allows for 1800 W on the 15-A wiring at 120V, but running 240V would allow for 3600 W of device power, potentially double the number of equivalent devices, although certain devices, like my kettle, would suck up double the current anyway, since it's basically just a resistor.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
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thanks...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik
 
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IRStuff, what actual power rating is your water heating device as stamped on the thing?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
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