LED's can be driven off AC directly, you just need a proper ballast resistor in series with the LED.
Which will generate a huge amount of heat. To run a single 3V, 100mA LED from US 120V would require an 1170 Ohm resistor. The LED would consume 0.3 W but the resistor would dissipate a whopping 11.7 W! Naturally the more LEDs in series the lower the power dissipation of the resistor (until you get to 40 3V LEDs, where no resistor would be needed).
Since we're dealing with fixed-frequency AC, why not use capacitive reactance instead? Very little heat, no muss, no fuss. A 2.2uF cap would work in the example above.
Also, most diodes, LEDs included, have a peak inverse voltage rating that would be exceeded with either a resistor or capacitor as the voltage dropping component. The solution, of course, is to use a pair of LEDs - one forward biased when the other is reverse-biased, and vice versa.
I modded you up, then thought about it for a sec. I think they're talking about using evanescent waves instead of classical mutual inductance. Evanescent waves separate the near field and far field when modeling antennas, btw.
... in an insurance ad the other day. They were saying something to the effect of "so-and-so got $OUR_INSURANCE, and when a leaky roof destroyed their Swedish Foam mattress, we sent them a check and now they have the Sleep Number bed. So-and-so's sleep number is 25."
AMD's 64-bit extensions, called amd64 internally by the Windows tools...
There's no need to insult Microsoft's programmers by calling them 'tools'. They have enough vitriol hurled at them already from all the users that experience BSODs and viruses.
The commenter that I replied to hinted at not realizing that there are plenty of educated people outside of his little world that pronounce the contraction as 'would of'.
I agree wholeheartedly that making that mistake hints at a basic misunderstanding of the mechanics of English. I didn't say I thought it was acceptable, only that I understand how it came about.
'We' are those of us who say it as the contraction "would've" as opposed to the sometimes stilted-sounding "would have". The contraction does sound like "wood-of", so I can see where an unthinking writer would spell it "would of".
Crispian Jago is also the creator of the awesome "Periodic Table of Irrational Nonsense" T-Shirt that I was wearing when a nice husband and wife pair of Baptists stopped by to invite me to their church. Uncomfortable!
How about applying kinetic energy = 1/2 m * v^2? 20,000 mi/hr is 8,941 m/s. a 1g pebble at that speed carries almost 40 kJ of energy - that's like getting hit with a 16 lb (7.257 kg) bowling ball at 234 mi/hr (105 m/s)!
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LED's can be driven off AC directly, you just need a proper ballast resistor in series with the LED.
Which will generate a huge amount of heat. To run a single 3V, 100mA LED from US 120V would require an 1170 Ohm resistor. The LED would consume 0.3 W but the resistor would dissipate a whopping 11.7 W! Naturally the more LEDs in series the lower the power dissipation of the resistor (until you get to 40 3V LEDs, where no resistor would be needed).
Since we're dealing with fixed-frequency AC, why not use capacitive reactance instead? Very little heat, no muss, no fuss. A 2.2uF cap would work in the example above.
Also, most diodes, LEDs included, have a peak inverse voltage rating that would be exceeded with either a resistor or capacitor as the voltage dropping component. The solution, of course, is to use a pair of LEDs - one forward biased when the other is reverse-biased, and vice versa.
I modded you up, then thought about it for a sec. I think they're talking about using evanescent waves instead of classical mutual inductance. Evanescent waves separate the near field and far field when modeling antennas, btw.
Here's an article that's heavy on buzzwords but may explain it.
... in an insurance ad the other day. They were saying something to the effect of "so-and-so got $OUR_INSURANCE, and when a leaky roof destroyed their Swedish Foam mattress, we sent them a check and now they have the Sleep Number bed. So-and-so's sleep number is 25."
Blatant negative branding.
...people who eat red meat were 60% more likely to die during the study period...
That's because none of the non-meat-eaters were at risk of choking on a barbecued brontosaurus rib.
...defenestrated it...
That must be one tough PC to survive being thrown out of a window.
You did the inverse - you threw Windows out of _it_.
AMD's 64-bit extensions, called amd64 internally by the Windows tools...
There's no need to insult Microsoft's programmers by calling them 'tools'. They have enough vitriol hurled at them already from all the users that experience BSODs and viruses.
...the scent of a failing selenium rectifier...
Oh my goodness, that _smell_! Distinctly different than most any other electrical smell for sure.
I prefer the climate in this version of Hell. I got married near here. The running joke is that I went through Hell to get married.
As I said in my biopic "Dune", fear is the mind-killer.
Shouldn't that be 'no such file or directory' since you're redirecting stdin?
If you want a wicked-fast kit car, check this out. No guarantees on being able to register it.
Isn't it difficult to get the patent number on each molecule of Nitrous Oxide?
Har har.
If you simply must have the patent number on the product, laser etch it.
If you simply must have the patent number on the product, laser etch it.
Today's waste product is tomorrows fuel.
Amen to that. Gasoline was once considered a waste product, and I hope that today's once-through nuclear 'waste' will be tomorrow's IFR fuel.
How about Chester Cheetah telling me that Cheetos are "Dangerously Cheesy"?
The commenter that I replied to hinted at not realizing that there are plenty of educated people outside of his little world that pronounce the contraction as 'would of'.
I agree wholeheartedly that making that mistake hints at a basic misunderstanding of the mechanics of English. I didn't say I thought it was acceptable, only that I understand how it came about.
'We' are those of us who say it as the contraction "would've" as opposed to the sometimes stilted-sounding "would have". The contraction does sound like "wood-of", so I can see where an unthinking writer would spell it "would of".
My guess would be that the leftover mash contained tetracycline and was eaten by the children.
Can anyone attest to the fact that the mash, after being relieved of its wort, would still contain tetracycline?
Today that sort of stuff is fed to livestock. Back then it was likely a good source of calories for humans.
Crispian Jago is also the creator of the awesome "Periodic Table of Irrational Nonsense" T-Shirt that I was wearing when a nice husband and wife pair of Baptists stopped by to invite me to their church. Uncomfortable!
I thought the same thing, but they apparently have an Special Temporary Authority (STA) granted: http://openbts.sourceforge.net/FieldTest3/STAGrant.pdf
How about applying kinetic energy = 1/2 m * v^2? 20,000 mi/hr is 8,941 m/s. a 1g pebble at that speed carries almost 40 kJ of energy - that's like getting hit with a 16 lb (7.257 kg) bowling ball at 234 mi/hr (105 m/s)!
You're likely correct! As much as I like food, why did I not think of that? Perhaps there's a taboo against eating one's God.
...the prosecutors made reference to the DSM.
Diving Spaghetti Monster? What powers can he _not_ obtain?
Scotty: "The more complicated the plumbing, the easier it is to stop up the drain."