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Rude Guy Gets Pepper Sprayed

Rude Guy Gets Pepper Sprayed

rbar says...

@enoch I agree he is an asshole for trying to get in front of her in the line (which started all this) and for trying (and succeeding) to agitate her. I may have missed it, I didnt hear any "rape culture". Perhaps I dont understand what is meant with that?

To me it seemed the lady was much more (Physically) aggressive than the gentleman. He was being a douche, she was being aggressive which just motivated him to agitate her more.

Tolerating physical action based on verbal abuse opens up a can of worms. All of a sudden we put the judging into the hands of random people. Everything someone says can then be interpreted as abuse and lead to physical reaction. What about a look? Is looking weirdly at someone considered abuse and therefor liable to physical deterrent? Is tasering someone considered ok next to peper spraying them? What about shooting? Where does it end?

That is a slippery slope. I am guessing here, but legally I think verbal abuse is a minor offence, physical action is a major offence.

Was it the employee of the shop or the agitating gentlemen that got fired?

Firing the employee of the shop for not stopping the gentlemen seems extremely harsh. You are depriving someone of their livelihood for not judging well enough if someone else goes over an arbitrary line.

If it was the gentlemen that got fired, well, still harsh. He was being an asshole for sure, but firing someone for that? Does that mean that everyone who is an asshole in traffic should get fired? I think there would not be many employees left.

Rude Guy Gets Pepper Sprayed

rbar says...

Uhm, is that not assault by the lady to the gentlemen? I dont think there is an excuse to physically attack anyone based on talk, even if you are a lady.

supreme skills - tops

rbar says...

@newtboy ah finally see what you mean. And yes you are right a Coke can would be stable and it could rotate. It is no longer considered a spinning top I think, so that is why the contestants didn't make it that way but for sure it would work.

If the can rotates I think the torque (force due to rotation) is in the same direction as gravity. (Where in the normal spinning top case gravity pulls the cg off center and torque back on.) In the can case both would move the cg back to equilibrium, Ie on center. there would be no precession at all. Every time some small Bump would make the cg move of the center axis it would be pulled back instantly.

I think it would work, and that it would take away the challenge ;-)

supreme skills - tops

rbar says...

@newtboy I think you are right if the spinning top would hang, ie its tip would be inverted (pointing upward, stuck to the plateau in some manner). Any movement away from center for the CG would be pulled back by gravity. No spinning required. However that is not a spinning top but a pendulum. As long as the tip is on top of the ground (pointing down) and not hanging the spinning top will be unstable and the only way to balance the top is to spin it no matter where the CG is.

supreme skills - tops

rbar says...

Good question. I think that the entire device is unstable no matter what, its impossible to keep it straight no matter where the point of gravity as long as it needs to balance on a single tip. So zero speed would mean tip over in all cases unless you make a more stable tip (square) which would mean it cant spin very well which means you havent made a spinning top.

You can find more about the physics of the spinning top here:
http://hyperphysics.phy-astr.gsu.edu/hbase/top.html
and here:
http://physics.stackexchange.com/questions/271/why-dont-spinning-tops-fall-over

So what is the optimal distance of the center of gravity to the tip?

There are several things working at the same time. Most importantly is the energy. You need to store as much energy as possible so that the top can spin for as long as possible. When the top slows spinning the friction at the tip becomes larger (the precession becomes bigger) so it starts to lose more energy and slows the spinning even more. You store energy by adding weight with a center of mass that is further away from the tip. When the top then "falls" the center of gravity moves down and reduces potential energy. Due to energy conservation kinetic energy goes up meaning speed of precession or of spinning goes up and creates a force pushing the top back up.

Off course, more mass means more friction at the tip, so there is for sure an optimal here, most likely depending on mass, size and shape of spinning top, etc.

Last but not least, more rotation speed I assume also means more friction, so its a trade-off.

If you move the center of mass down below the tip, well, if you move it as far off as you would above, the energy you can save is about the same, but the entire thing would be harder to build and you would need to make sure the sides fit around the ground plateau. Also, when the precessions become bigger the sides will hit the plateau, meaning game over.

In the end you are better of keeping the center of gravity above the tip point.

newtboy said:

Hmmm. I wonder why neither team decided to lower the center of gravity below the contact point, since they would be spinning on the tiny raised cylinders? It seems it would be easy to make the outer ring hang below the point, so it would stay upright at 0 rpm. Does that somehow make it unstable when you spin it?
*quality craftsmanship and design

supreme skills - tops

Orangutan Builds Hammock

rbar says...

Orangutans build beds in trees every night in the wild using branches and leaves. They are better at building beds than us. Its great to see such ingenuity and sad to see it locked up.

Permeable Concrete? It's like magic!

rbar says...

This type of concrete (or something very similar) has been in use since 1973 in the Netherlands. Currently about 90% of the Dutch highways use this. Its big advantages are less noise, less aqua planning and more visibility due to less water from tires. Its disadvantages are somewhat less grip, more wear and issues with freezing. The freezing doesnt necessarily break the concrete but any salts used to de-ice the road will also be washed away meaning that the top layer of the road will often be very slippery. In the Netherlands, with between 23 and 46 days with temperatures below zero on average, the amount of trouble that causes is acceptable compared to the advantages.

How I won the lottery

Instantly See Which Side of Your Car the Gas Tank Is On

rbar says...

Older cars dont have the arrow. They show where the tank is by having the arm of the little gas symbol on the side where the tank is. So in the above movie, its on the right, where the arrow is ;-)

thedeusmachine (Member Profile)

rbar says...

Hi thedeusmachine, I got a message the cashback short was dead. The short seems to be on your name now so i cant update it anymore, can you update the link to below?

Its this one:
http://videosift.com/video/Cashback-Oscar-nominated-short-film

Update embed to:
<iframe frameborder="0" width="480" height="270" src="//www.dailymotion.com/embed/video/xthts" allowfullscreen></iframe>
Cashback door drukskill

From: http://www.dailymotion.com/video/xthts_cashback_creation

Thanks!
Kind regards,
RBAR

Pixar short - blue umbrella - Pixar is back!

rbar says...

I hope Pixar never went away, but it has been a while since I saw something so artful and powerful from them. And I think it is the first time umbrella was watchable for free? Well, in any case hope it made you happy to see it again

The Middle East problem "explained"

Insane Himalayas Bus Ride - not for the faint hearted



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