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Skyler4856

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27 minutes ago, MaverickSawyer said:

2 Farad capacitor

whaaaat

what's the voltage ? Surely it's just a battery ?

EDIT : After short googling it appears to be used for high-power sound systems.

Edited by YNM
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6 hours ago, MaverickSawyer said:

Hmmm. Found a 2 Farad capacitor (yes, you read that right) at the rummage sale store downtown for US$30. Was sorely tempted to buy it, but I'm not sure quite what I'd need it for, other than the sheer "what??!?" factor.

Make an railgun. 

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8 hours ago, YNM said:

whaaaat

what's the voltage ? Surely it's just a battery ?

EDIT : After short googling it appears to be used for high-power sound systems.

24V. I did the math upon finding it and quickly realized that the cap could store energy to probably start a car.

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4 minutes ago, MaverickSawyer said:

24V. I did the math upon finding it and quickly realized that the cap could store energy to probably start a car.

Your capacitor is not this, but here is some fun information...

 

In the EU, if your capacitor meets these criteria, then it is classified as "dual use" and possession/use/manufacture/sale is strictly controlled, due to their utility in building components for nuclear detonators:

 

High energy storage capacitors as follows:
N.B.: SEE ALSO 3A201.a.
 a. Capacitors with a repetition rate of less than 10 Hz (single shot capacitors) and having all
of the following:
 1. A voltage rating equal to or more than 5 kV;
 2. An energy density equal to or more than 250 J/kg; and
 3. A total energy equal to or more than 25 kJ;
 b. Capacitors with a repetition rate of 10 Hz or more (repetition rated capacitors) and
having all of the following:
 1. A voltage rating equal to or more than 5 kV;
 2. An energy density equal to or more than 50 J/kg;
 3. A total energy equal to or more than 100 J; and
 4. A charge/discharge cycle life equal to or more than 10,000; 

 

 

Ref: 

Regulation (EC) No 428/2009

http://trade.ec.europa.eu/doclib/docs/2010/november/tradoc_146860.pdf

 

 

(skimming that document, I learned the term "splat quenching", that was fun :) )

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17 hours ago, magnemoe said:

Make an railgun. 

Having had some time to dwell on it... the bird feeder out back keeps getting raided by squirrels. I mean, an electric fence transformer would probably be more than adequate to make the squirrels thing twice (or thrice, or more...) before raiding the feeder again, buuuut... A coilgun just sounds so much cooler. :D 

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Probably depends on what one puts in it. And there may be "squirrel proof" designs out there.

Can be interpreted as an example of negative environmental effects of feeding wild birds, as sorry as i am to state this ...

Edited by Green Baron
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8 hours ago, Gargamel said:

Squirrels are determined little suckers. 

A fundamental mental difference between the American and the Russian cultures.
In Russian culture squirrels are a standard of cuteness. Even more than cats who are ambivalent.

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On 11/14/2018 at 1:02 AM, Green Baron said:

Probably depends on what one puts in it. And there may be "squirrel proof" designs out there.

Can be interpreted as an example of negative environmental effects of feeding wild birds, as sorry as i am to state this ...

There is no such thing as squirrel proof... merely highly squirrel resistant. Nature will always evolve a better squirrel.

 

... Hmm. Same statement applies to idiots, too. :D 

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14 hours ago, kerbiloid said:

A fundamental mental difference between the American and the Russian cultures.
In Russian culture squirrels are a standard of cuteness. Even more than cats who are ambivalent.

I would find it hard to disagree with anybody who ranks squirrels high on the cuteness scale, but they are ingenious determined acrobatic monstrosities that will not let any engineer defeat them. 

But here's what I like to do with squirrels.    I'll find a couple as they are collecting and burying their nuts for the winter.   When they aren't looking, I go and replace the nuts with a grilled cheese sandwich.  Then, in the spring, when they go to dig up the nuts, I make sure I have a camera ready to capture the look of total shock and surprise on their fuzzy little faces as they dig up my sandwich.   So worth the effort.    

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21 hours ago, Gargamel said:

I would find it hard to disagree with anybody who ranks squirrels high on the cuteness scale, but they are ingenious determined acrobatic monstrosities that will not let any engineer defeat them.

North American squirrel:

Spoiler

squirrel1.jpg

European squirrel:

Spoiler

16396163086_a369d9fb5d_b-1024x683.jpg

So it's not just the squirrel behavior, but entirely different imagery one gets when thinking about squirrels in America vs Europe, especially Eastern Europe.

 

 

Edited by K^2
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Fun (?) fact: the American Squirrel was introduced in Europe and seems to be fitter than the European red version. It is replacing it.

Better memory, eh ? :cool: Or ruthless enough to rob bird feeders ?

https://www.researchgate.net/publication/242084905_Introduction_of_the_American_grey_squirrel_Sciurus_carolinensis_in_Europe_A_case_study_in_biological_invasion

 

Edited by Green Baron
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On 11/15/2018 at 10:38 PM, Gargamel said:

 but they are ingenious determined acrobatic monstrosities that will not let any engineer defeat them. 

Not all of them. Be careful, strong image below!

Spoiler

I mean it. Really.

Spoiler

Dude... This will keep you awake in the bed all night! 

Spoiler

Are you really this brave?

 

 

 

 

Edited by Lisias
Another source for the image, the previous had also unaproprieted content
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I met a woman a while ago who was from South America.  She just loved the squirrels here in Massachusetts.  She complained that "all we have back home are monkeys".  The squirrels here are a menace to bird feeders but not nearly as much as the bears.  Bears just love bird feeders this time of year.  I know someone who left a 25 pound bag of black oil sunflower seeds on her porch for just 5 minutes and turned around just in time to see a bear making off into the woods with it! 

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7 hours ago, Green Baron said:

Or ruthless enough to rob bird feeders ?

I think that's a good chunk of it. European squirrels are a lot more shy with humans, in my experience. I've never seen one closer than on a tree branch five meters off the ground, hiding behind the trunk from me as if I still pose some sort of a danger. In contrast, squirrels in N.A. tend to feel pretty comfortable looking for food 3 meters from a person, unless said person starts moving towards them. And that's in suburbs. In some of the more touristy places, where people feed them, they tend to get almost as shameless as pigeons. I've had one come up to me in Boston, and when I squatted to take a closer look, it actually grabbed my hand to see if I have any food for it. Once it saw no food, it got disappointed and left. Can't picture European squirrel pull something like that.

That said, in some parts of USA (e.g. Midwest, parts of Cali), Canadian black squirrels seem to be pushing out the gray locals. That seems to be just stronger territorial aggressiveness, though, rather than any special interaction with humans. Unless there is some more subtle adaptation that I'm not aware of.

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