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Bill Maher: Who Needs Guns?

jubuttib says...

If it came down to that, I might just be willing to take bombings over shootings.

After a bit of Google and Wiki work, it really looks like A) bombings are insanely rare compared to shootings B) tend to result in lots of injured but surprisingly few deaths (the main exceptions were incidences where hundreds or even thousands of kg of explosives were used and a few incredibly successful train bombings with lots of organization, planning and especially shrapnel) C) tend to fall into the purview of organized groups of larger terrorism groups rather than lone nutters (exceptions exist of course).

Neither is good, but shootings would on the surface seem to result in comparatively more deaths than injuries (and more deaths overall, even in countries with strict gun laws), guns are way more prolific and accessible (even in countries with strict gun laws), and require a lot less preparation to be successful at targeting many people.

In summary: ... Eh...

Buy These Tickets Or I Take Your Car

It's Poop!?

jubuttib says...

While I can't say I like it personally, it's not that bad, and definitely only needs a very thin layer. It's more a spice, not a foodstuff. As a kinda related example I love soy sauce in my noodles or rice, but I bloody well wouldn't drink it out of the bottle.

NaMeCaF said:

No, see that's the thing. It tastes like crap if you put that much on! With just a smidge and plenty of butter it tastes bloody marvellous.

Pull my finger! Scientists solve knuckle-cracking riddle

jubuttib says...

Not quite, he (Donald L. Unger) won an Ig Nobel prize, a satirical version of the Nobel prize, given to "honor achievements that first make people laugh, and then make them think". Basically anything that sounds way too silly but can still yield useful knowledge.

While silly, it's still (usually) all based on proper scientific method, and there's even an example of a man who first won the Ig Nobel prize in physics in 2000 (for levitating a frog with magnets), and then later went to win the Nobel prize in physics together with Konstantin Novoselov for their work on graphene. =)

lucky760 said:

I believe someone won a Nobel prize for spending several decades of his life cracking the knuckles of one hand and just that one hand every day to see if there are really any negative effects from knuckle-cracking.

In his case there weren't.

Minute Physics: How Do Airplanes Fly?

jubuttib says...

There's some debate on the exact phenomenons at play and their extents, but the gist of it is correct, it's not like they have "no idea" how it works. An airfoil moving through air (or any other fluid, same principles work in water as well) generates a higher pressure below it and a lower pressure above it, which results in lift. This can be done even with simple flat plank by using angle of attack, or more effectively if you shape it like a good airfoil. Similarly the wings in racing cars do the same thing but flipped upside down, pushing the car down to the ground (though exploiting underbody aerodynamics can be much more effective if regulations allow it).

The only thing that really bothered me in the video was the insistence on the angle of attack being required for lift. Some planes are so light and have wings that produce so much lift (due to size and shape), that at high speeds they actually need to have negative angle of attack to fly level. If the plane didn't point down a bit it'd just keep climbing higher and higher.

plentyofdice said:

So THIS is how wings work? I am so confused after watching the guy from NASA (paper plane enthusiast guy) explain that no one really has any idea how they work.

the Millennium Falcons look was a last minute design

TARSplay

jubuttib says...

The robots were in some ways some of the most reasonable ones I've seen in movies. The balancing when moving in the way shown here would pose definite problems, but they had a variety of locomotions (I liked the fastest rotating one the best) and the joints between the pieces at least looked like they'd be fairly easy to make very solid and robust. Though the fittings between the pieces looked pretty tight, so basically if you got a rock stuck in there... Yeah... Some issues.

Other than that overall the movie was a very meh experience, and I was so disappointed by some of the physics (mostly the basic one, particularly the airlock explosion somehow causing the craft/station to de-orbit... How exactly?) that I almost wrote it off at that point. Luckily the ending kinda pulled it together again so it wasn't on the whole unpleasant, even though they hammered it in way too much.

So, some smartass went and reinvented the wheel ...

jubuttib says...

Yeah, "applicable only to the very lightest of electric vehicles". Something like that would at least have a chance of working. Basically something like a Segway, an electric bike, a small cart/kart/trike, something like that. Though how much of a weight save compared to loss of driving dynamics/stability/safety you'd get is a bit iffy, the suspension bits in a 200 pound vehicle are already very light.

But yeah, something like that might work.

newtboy said:

OK, I don't disagree on any point, except the assumption that an electric car MUST be a 1000KG fully loaded passenger car.
I was thinking more of the non-highway legal, neighborhood kind that might weigh 200lbs.+- where saving 75-100 lbs would make a huge difference, and minimal suspension would still be OK.

So, some smartass went and reinvented the wheel ...

jubuttib says...

I think that at best this would be applicable only to the very lightest of electric vehicles (something in the "motorcycle" weight class, even half a ton is probably too heavy), and I have my doubts about even those, even when completely disregarding the sideways forces.

With a system like this you do not want more than a few cm (about an inch, at a guess) of suspension travel from when the car is lifted in air to the car at rest (= 1G vertical load), just from the weight of the car compressing the springs. If you have more the springs (which the loops naturally are) have to compress a lot with each revolution, which strains them, heats them, isn't good for rolling resistance, etc.

If we assume a 1000 kg car with a 50/50 weight distribution, to get about 2 cm of suspension travel the spring stiffness would be about comparable to a high level GT racing car. Comparing to high level sports cars, the street going Porsche 911 GT3 RS car, which is regarded as a pretty stiff, racy and track oriented vehicle has something in the region of three times that much travel, a normal commuter car can have way over 10 cm due to soft, comfort oriented springs.

So you can't spring a proper car with just these because it'd require it to be too stiff (also I can foresee shock absorption issues). Another problem is the 360 degree springy nature of it. You really don't want car tyres to move much aside from up and down. These have the problem that when you brake, the forces will try to push the axle forwards in relation to the wheel (i.e. the wheel moves backwards while braking), and the reverse when accelerating. You'd be (possibly) drastically changing the wheelbase of the car during acceleration and braking, which could have catastrophic results for handling in extreme situations. Many if not most cars these days are capable of braking at over 1 G, as long as they have decent tyres, so the front-back movement could be bigger than the up-down movement.

So yeah, doesn't really sound like a workable solution as the ONLY spring system on a car. Having some springiness in the tyres (either in the wheel itself of just having larger profile tyres, like we used to back in the day) can be helpful for comfort and even handling in some cases, but springing the car only via the wheels isn't a good idea, you really want to be able to control the wheels better than that.

newtboy said:

If they do well, perhaps this is a way to eliminate suspension in electric vehicles, reducing weight but keeping a smooth ride.

Japan's most famous Katana maker Kobayashi

jubuttib says...

Damn that music is annoying. It covers up the most beautiful little *ting* sound I've ever heard. It's a nice dichotomy that such a beautiful and delicate sound is made by forging a piece of metal on a large anvil by big ass hammers. =)

Get Lucky Played by 10 Epic Famous Guitar Players

jubuttib says...

As great as this video was, the impression I got with many of those players was more "how to adapt player X's most famous solo/riff to Get Lucky".

Still fun to listen to. =)

creepy talking raven

Oculus Rift "Crescent Bay" Prototype Hands-On + Impressions

jubuttib says...

You gotta love Palmer's honesty. "... your gaming headphones are garbage, sorry..." "Traditional game pads are not good virtual reality input devices, you really need something better. Anyone who's ever used a keyboard and mouse can tell you, game pads just don't stack up, they're pretty shitty."

I mean, it's all true of course, and nothing new, but it's refreshing to hear people in his position (something of a leader figure in the industry) to say it out loud. =)

Deadpool - Test Footage

Who knew metal milling machine could be such fun?

jubuttib says...

A lot less wasteful, yeah, but there's quite a big difference in the structural integrity of cast and machined parts, so for many applications casting is just not an option.

Still, recycling and whatnot.

Payback said:

Aluminium is one of the easiest materials to recycle. Although I'd say molding most of the shape and "cleaning" up the piece would be less wasteful of cutting edges and power...



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