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You can make a tube lamp light up a bit by taking the voltage from several 9 V batteries connected in series, but you probably don't want to combine enough batteries to equal the intended voltage.
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Please define or approximate "several."hilbert2 said:
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Tom.G said:
Even one battery will make it produce some light, two or three a bit more.
Swamp Thing
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hilbert2 said:
You could always put a resistor in series.
Would about 50 volts be enough to see some glow? If so, you could safely let the current pass through you from fingertip to fingertip. (Umm, maybe not if you have any kind of heart condition). Or, you and a couple of friends could join hands to form the circuit... a modern version of those 18th century electrostatic parlor tricks.
You could even combine it with some Victorian occultism and, ah, "conduct" an electric séance.
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Keith_McClary
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This page suggests you need hundreds of volts if you don't preheat the electrodes.hilbert2 said:
There is an LED replacement.
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Swamp Thing said:
- Not advisable in terms of safety
- it would limit the current so much that you won't see anything.
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Keith_McClary said:
As far as I know, the longer bathroom tube lamps often have this kind of "igniter" at one end to start the current flow.
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Since that is a 2-pin device it is called a Starter (in the US), it is a Normally Closed thermal switch that connects power to the filaments (heaters) in the tube. This vaporizes some of the Mercury in the tube, which is the main conductor during operation.
After a few seconds, the Starter heats up enough to open, removing power from the filaments and applying the high voltage across the ends of the lamp. The high voltage is sufficient to ionize the the Mercury vapor and other gasses in the tube to a plasma, thus emitting UltraViolet light.
The UV light excites the phosphors coating the inside surface of the tube to emit visible light. Different combinations of phosphors are used for different Color Temperatures such as Warm White, Cool White, Daylight, etc.
There are also Instant Start lamps and circuits that do not need a Starter or an Ignitor.
Cheers,
Tom
After a few seconds, the Starter heats up enough to open, removing power from the filaments and applying the high voltage across the ends of the lamp. The high voltage is sufficient to ionize the the Mercury vapor and other gasses in the tube to a plasma, thus emitting UltraViolet light.
The UV light excites the phosphors coating the inside surface of the tube to emit visible light. Different combinations of phosphors are used for different Color Temperatures such as Warm White, Cool White, Daylight, etc.
There are also Instant Start lamps and circuits that do not need a Starter or an Ignitor.
Cheers,
Tom
etotheipi
TIL that the empty set ##\varnothing## is a function!
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TIL: A Butt is (ok, was) a real unit of measure. 1 Butt ≈ 500 litres of wine. So drinking a Butt-load of wine probably isn't a great idea.
Keith_McClary
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Must... resist... temptation to post pictures of certain celebrities as confirmatory evidence of this...Keith_McClary said:
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a Butt-load of Beer would be worse, as there are two hogsheads to a Butt and a hogshead of beer is 64 gallons, vs. 63 gallons for wine. ( imagine the trips to the restroom!)DaveE said:
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TIL... "de Broglie" is pronounced "de Broy" (rhymes with destroy). [Thanks to Sabine Hossenfelder's latest video.]
But,... WTF?? How do you get "oy" out of "oglie".
Oh well, English can be incomprehensibly weird too, at times.
But,... WTF?? How do you get "oy" out of "oglie".
Oh well, English can be incomprehensibly weird too, at times.
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Because it's not English. He was French.strangerep said:
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I'll tell you after you tell me how you get 10 different sounds out of "ough".strangerep said:
rough, through, thorough, borough, cough, bough, thought, hiccough, ...
The French love to write a few more letters than they pronounce at the end of words.
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TIL about thr Conway base 13 function.
The intermediate value theorem says that a continuous function will reach every intermediate value between f(a) and f(b) somewhere between a and b. But is the converse also true? Is a function that reaches every intermediate value (for any a,b) continuous? No, and the above function is a counterexample.
The intermediate value theorem says that a continuous function will reach every intermediate value between f(a) and f(b) somewhere between a and b. But is the converse also true? Is a function that reaches every intermediate value (for any a,b) continuous? No, and the above function is a counterexample.
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With just a quick read of the Wikipedia article, it looks like that assertion is a fallacy.
They are redefining some characters that are numeric in base 13 (specifically "+", "-", ".") as operators or delimiters in base 10.
As an example the American word 'Corn.'
(following extracted from:
https://forum.thefreedictionary.com/postst137875_Maize-Vs-Corn.aspx)
Maize is big green leafy plants with yellow cobs.
In America this is called corn.
.
.
In the UK, that is called maize, but the vegetable on the stalk is called corn on the cob,
.
.
In the UK, corn is a grain.
It commonly means wheat, but it can apply to any grain.Or... maybe I missed something?
They are redefining some characters that are numeric in base 13 (specifically "+", "-", ".") as operators or delimiters in base 10.
As an example the American word 'Corn.'
(following extracted from:
https://forum.thefreedictionary.com/postst137875_Maize-Vs-Corn.aspx)
Maize is big green leafy plants with yellow cobs.
In America this is called corn.
.
.
In the UK, that is called maize, but the vegetable on the stalk is called corn on the cob,
.
.
In the UK, corn is a grain.
It commonly means wheat, but it can apply to any grain.Or... maybe I missed something?
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It's just a way to describe how the function assigns values to numbers. To find f(a), write a in base 13, replace A B C with symbols, then assign f(a) based on the described algorithm. Where is the problem?Tom.G said:
I don't see how this would have anything to do with the way corn is described in English.
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Yup,
Goodnight.
I read only thru the "Sketch of definition" section. Reading the rest of the article, you are probably correct. I'll go to bed now.Tom.G said:
Goodnight.
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TIL that cheetahs were originally american cats who emigrated to Africa.
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LOL. I was thinking femtoseconds! Clearly I have NO IDEA AT ALL how this machine works.Keith_McClary said:
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The main loop is 26 kilometers. At 300,000 km per second, that's about 10 laps per millisecond. You need your beam line particles (a substantial fraction anyway) to survive for at least a couple of laps, otherwise you might as well build a linear accelerator instead.DaveE said:
Surviving for 10 hours -- 360 million laps if I haven't slipped a digit -- is impressive. [Of course I doubt you would keep the same particles in the beam that long. The quoted figure is likely just extrapolation from the loss rate you get for the short intervals you actually use]
Caveat: I'm not an expert, just applying high school physics knowledge to the situation.
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Collisions with the opposing beam are indeed an important loss mechanism, and of course it's one you do not want to reduce.
Refilling the LHC takes at least two hours but three hours is more typical (and four to five can happen, too), so this long lifetime is important. The optimal time to dump the beam and refill comes after about 15 hours.
Refilling the LHC takes at least two hours but three hours is more typical (and four to five can happen, too), so this long lifetime is important. The optimal time to dump the beam and refill comes after about 15 hours.
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Some railroad trivia
1961: Missouri Pacific acquires the rail industry’s first solid-state computer, an IBM 7070. Railroads will become one of the earliest major users of computer technology.
1968: Southern Pacific acquires the rail industry’s first locomotive engineer training simulator.
1970: In June, the giant Penn Central declares bankruptcy. At the time, it was the biggest corporate bankruptcy in U.S. history. I remember that day. It precipitated the bankruptcy of many other railroads in the NE US, including the Lehigh Valley, Erie Lackawanna, Reading, Central of New Jersey, Lehigh and Hudson River and the Pennsylvania-Reading Seashore Lines.
https://en.wikipedia.org/wiki/Penn_Central_Transportation_Company#Bankruptcy
1976: The Railroad Revitalization and Regulatory Reform Act creates the Consolidated Rail Corp. (Conrail) from six bankrupt Northeast railroads. The legislation also includes regulatory reforms that are supposed to make the rail regulatory system more responsive to changed circumstances.
1980: Congress passes the Staggers Rail Act, reducing the Interstate Commerce Commission’s regulatory authority over railroads and sparking competition that stimulates advances in technology and a restructuring of the industry, including creation of hundreds of new shortline and regional railroads using rail lines spun off from larger railroads.
1996: After 108 years, the Interstate Commerce Commission goes out of existence and is replaced by the Surface Transportation Board, which assumes responsibility for remaining regulation of rail rates and services.
2008: Coal again becomes the top source of U.S. rail industry revenue, overtaking intermodal (which had taken over the top spot in 2003). Class I railroads originate a record 879 million tons of coal.
https://www.aar.org/chronology-of-americas-freight-railroads/
1961: Missouri Pacific acquires the rail industry’s first solid-state computer, an IBM 7070. Railroads will become one of the earliest major users of computer technology.
1968: Southern Pacific acquires the rail industry’s first locomotive engineer training simulator.
1970: In June, the giant Penn Central declares bankruptcy. At the time, it was the biggest corporate bankruptcy in U.S. history. I remember that day. It precipitated the bankruptcy of many other railroads in the NE US, including the Lehigh Valley, Erie Lackawanna, Reading, Central of New Jersey, Lehigh and Hudson River and the Pennsylvania-Reading Seashore Lines.
https://en.wikipedia.org/wiki/Penn_Central_Transportation_Company#Bankruptcy
The Penn Central Transportation Company was created in 1968 via a merger between the Pennsylvania and New York Central railroads. The Pennsylvania Railroad dated back to 1846, and the New York Central railroad dated back to 1853.
1976: The Railroad Revitalization and Regulatory Reform Act creates the Consolidated Rail Corp. (Conrail) from six bankrupt Northeast railroads. The legislation also includes regulatory reforms that are supposed to make the rail regulatory system more responsive to changed circumstances.
1977: The Chicago, Milwaukee, St. Paul and Pacific Railroad (CMStP&P), aka the "Milwaukee Road" (reporting mark MILW) filed for its third bankruptcy in 42 years on December 19. It suffered from poor management for about 7+ decades. Operations ended west of Miles City, Montana on February 29, 1980. Ultimately, lines were abandoned and the surviving railroad broken up and sold to Soo Line (a subsidiary of CP), BN (now BNSF), and other smaller railroads.
The BN was formed in 1970 from the merger of Great Northern; Norther Pacific; Chicago, Burlington & Quincy (CBQ) and Seattle, Portland & Spokane (SPS)
The Milwaukee Road secured concessions from the BN merger, which were intended to preserve competition in the Norther States and Pacific Northwest. However, MILW failed to ensure the concessions were met, and the ICC failed to enforce, in addition to having a rundown physical plant.
1980: Congress passes the Staggers Rail Act, reducing the Interstate Commerce Commission’s regulatory authority over railroads and sparking competition that stimulates advances in technology and a restructuring of the industry, including creation of hundreds of new shortline and regional railroads using rail lines spun off from larger railroads.
During the 1980s, the railroad industry began a merger trend that now sees essentially 7 class I freight railroads: BNSF and UP in the west, CP, CN and KCS in the middle and north, and CSX and NS in the east.
1996: After 108 years, the Interstate Commerce Commission goes out of existence and is replaced by the Surface Transportation Board, which assumes responsibility for remaining regulation of rail rates and services.
2008: Coal again becomes the top source of U.S. rail industry revenue, overtaking intermodal (which had taken over the top spot in 2003). Class I railroads originate a record 879 million tons of coal.
https://www.aar.org/chronology-of-americas-freight-railroads/
In 2020, coal shipments have dropped about 17% from 2019 levels and about 30% from 2018 levels.
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TIL about Chaos Engineering and the Simian Army. 
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TIL how to write unmaintainable code. Y'all have probably seen this, but it's new to me and HILARIOUS.
A couple of randomly chosen excerpts:
Åccented Letters
Use accented characters on variable names, e. g.
typedef struct { int i; } ínt;
where the second ínt’s í is actually i-acute. With only a simple text editor, it’s nearly impossible to distinguish the slant of the accent mark.
Reuse of Global Names as Private
Declare a global array in module A and a private one of the same name in the header file for module B, so that it appears that it’s the global array you are using in module B, but it isn’t. Make no reference in the comments to this duplication.
A couple of randomly chosen excerpts:
Åccented Letters
Use accented characters on variable names, e. g.
typedef struct { int i; } ínt;
where the second ínt’s í is actually i-acute. With only a simple text editor, it’s nearly impossible to distinguish the slant of the accent mark.
Reuse of Global Names as Private
Declare a global array in module A and a private one of the same name in the header file for module B, so that it appears that it’s the global array you are using in module B, but it isn’t. Make no reference in the comments to this duplication.
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