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Modes of Transportation for Children - Water Transportation

newtboy says...

It is ridiculous to assume a child that's never seen a bicycle can read the word bicycle.....especially if they're taught by videos like this that misspell simple words like yacht.

Terrible flaw in expensive crowdfunded padlock

AeroMechanical says...

Meh, padlocks are not for securing valuable property or for securing property against someone with any sort of tools at all. They are for preventing opportunistic theft. 30 seconds to defeat the lock is plenty long enough for that. Of course, that is a pretty stupid design, so good video nonetheless. If I owned one already, a little solder or permanent loctite on the inner screws would probably do the trick.

Mostly though, The lock company lost me at $100 for the lock. A traditional dial is not *that* hard to work and I'd be worried about false negatives and dead batteries even with a high-quality finger print reader. Just buy a $10 padlock at the hardware store to lock up your garbage cans, or proper u-lock or quality cable to lock up your $600 bicycle (ie, something that will require 15 minutes to defeat).

NY Police Ram Cyclist And Make Up Charges

AeroMechanical says...

That seems to be the police maneuver with bicycles. They've done that to me before: they come up along side you and then swerve to cut you off so unless you are on your toes you will collide with them. Heaven forbid they should just flash their lights and tell you to stop when they can just assume everyone is a deadly dangerous criminal. I blame Daryl Gates.

Protest violence in Seattle. Alt-Right Bro defeated

nanrod says...

Actually he's just a bicycle riding Seattle leftist trying to dispose of his protest sign in an environmentally friendly way

16 seconds: The Killing of Anita Kurmann

drradon says...

I have commuted to work by bicycle for years - gotten "tagged" a couple of times by careless drivers with no major injuries...
But, I don't much care what the law says, if you have a large vehicle of any sort in your vicinity, it's up to you to know what the truck is doing and going to do and be ready to react accordingly. Any messaging that argues otherwise is just plain stupid. Maybe the driver sees you, and maybe not - maybe he's been driving too many hours with too little sleep. Maybe he's arguing with his boss or his girlfriend - doesn't make any difference what he's doing - if you want a long and reasonably painless bicycling career, it's up to you to judge the driving conditions and safety of your situation and placement at all times...

16 seconds: The Killing of Anita Kurmann

BigAlski says...

Well I drive trucks and make this type of "button-hook" turn a lot. First of all if it were a car he would leave his trailer less than 4 feet from the curb in back so a car can't sneak by. They teach you this in truck school. He had his signal on and I drive through a college housing area all the time and make a turn like this with young people on my right a lot. She probably should have stopped and let him turn, him being in busy traffic he has to turn with the flow of traffic which might be slower than a bicycle. That said, of course he has to monitor the cyclist (I also ride bicycles in the big city) and stop immediately if she didn't yield or time his approach so she goes ahead of him. So ya, from truck driving school to my next work day (tomorrow) the driver is ALWAYS at fault if he hits anything on his right turning no matter who has the right a way. Sad case

One Kick Ass Donald Trump Float In Parade

StukaFox says...

It's the Fremont Solstice Parade in Seattle's Fremont neighborhood.

It's famous for the Naked Bicycle Ride that proceeds the festivities.

MilkmanDan said:

Fun -- any idea where it was?

The cropping and general video quality makes it look sort of like old footage. Kinda reminded me of JFK assassination video, lol

**edit**
Googling "Clear Cut Plastics Inc." shows that storefront in Seattle. So that makes a lot of sense.

16 seconds: The Killing of Anita Kurmann

Buttle says...

I agree with Mass Bike that the truck driver was responsible. Not sure that he should be criminally charged, that's a really big hammer to use on someone that almost certainly did not intend any harm. But he wasn't even cited, although he left the scene. He called the Boston police many hours later, from New Jersey.

That said, I would advise any cyclists to avoid ever putting themselves in the position that Dr Kurmann found herself in. It is dangerous to ride beside large vehicles with limited visibility, as we see. Also good to note that semi trucks frequently swing left to set up a right turn -- I don't believe she realized the danger she was in until the truck was close to actually passing in front of her.

The symbol in the middle lane is a "sharrow", which really indicates that the middle lane is not a bike lane. The sharrow is supposed to indicate to motorists that bicycles may be expected in the lane, and to remind cyclists that they are allowed to use it. The Boston police report gets this wrong, irresponsibly making the driving public stupider. At the time of the crash the right lane was used as a turn lane, and there was a bus stop just before the crash site, making it likely that cyclists would use the middle lane.

It's fun to say that you never trust anyone, but that can't literally be true. For example, I trust thousands of drivers standing at red lights or stop signs not to charge out and run me over. It would be almost impossible to move in traffic without relying on most drivers to do the right thing most of the time.

Digitalfiend said:

Sad video for sure (the music was a bit much though).

Kind of a tough call - I do think the truck driver deserves the majority of the blame and should at the minimum be charged with a hit and run - and probably more - as he did pass the cyclist and clearly did not proceed with any due caution on that turn.

With that said, as an avid cyclist myself, I trust NO ONE while riding. Looking at the video, there seems to be a bike lane symbol in the middle lane, suggesting that cyclists proceeding through the intersection should be using that lane. Now I don't think that is enforced by law, but if that is what the symbol is there for, this would be a perfect illustration as to why. Also, if you look even closer, it appears the truck had his indicator on before she pulled up beside him; i.e. she should have seen his indicator. I hate to put any blame on that poor woman and - I really hate to say this - this video only goes to show that both parties were at fault.

Patrick Stewart Looks Further Into His Dad's Shell Shock

MilkmanDan says...

Possible, but I don't really think so. I think that the Medical minds of the time thought that physical shock, pressure waves from bombing etc. as you described, were a (or perhaps THE) primary cause of the psychological problems of returning soldiers. So the name "shell shock" came from there, but the symptoms that it was describing were psychological and, I think precisely equal to modern PTSD. Basically, "shell shock" became a polite euphemism for "soldier that got mentally messed up in the war and is having difficulty returning to civilian life".

My grandfather was an Army Air Corps armorer during WWII. He went through basic training, but his primary job was loading ammunition, bombs, external gas tanks, etc. onto P-47 airplanes. He was never in a direct combat situation, as I would describe it. He was never shot at, never in the shockwave radius of explosions, etc. But after the war he was described as having mild "shell shock", manifested by being withdrawn, not wanting to talk about the war, and occasionally prone to angry outbursts over seemingly trivial things. Eventually, he started talking about the war in his mid 80's, and here's a few relevant (perhaps) stories of his:

He joined the European theater a couple days after D-Day. Came to shore on a Normandy beach in the same sort of landing craft seen in Saving Private Ryan, etc. Even though it was days later, there were still LOTS of bodies on the beach, and thick smell of death. Welcome to the war!

His fighter group took over a French farm house adjacent to a dirt landing strip / runway. They put up a barbed wire perimeter with a gate on the road. In one of the only times I heard of him having a firearm and being expected to potentially use it, he pulled guard duty at that gate one evening. His commanding officer gave him orders to shoot anyone that couldn't provide identification on sight. While he was standing guard, a woman in her 20's rolled up on a bicycle, somewhat distraught. She spoke no English, only French. She clearly wanted to get in, and even tried to push past my grandfather. By the letter of his orders, he was "supposed" to shoot her. Instead, he knocked her off her bike when she tried to ride past after getting nowhere verbally and physically restrained her. At gunpoint! When someone that spoke French got there, it turned out that she was the daughter of the family that lived in the farm house. They had no food, and she was coming back to get some potatoes they had left in the larder.

Riding trains was a common way to get air corps support staff up to near the front, and also to get everybody back to transport ships at the end of the war. On one of those journeys later in the war, my grandfather was riding in an open train car with a bunch of his buddies. They were all given meals at the start of the trip. A short while later, the track went through a French town. A bunch of civilians were waiting around the tracks begging for food. I'll never forgot my grandfather describing that scene. It was tough for him to get out, and then all he managed was "they was starvin'!" He later explained that he and his buddies all gave up the food that they had to those people in the first town -- only to have none left to give as they rolled past similar scenes in each town on down the line.

When my mother was growing up, she and her brothers learned that they'd better not leave any food on their plates to go to waste. She has said that the angriest she ever saw her dad was when her brothers got into a food fight one time, and my grandfather went ballistic. They couldn't really figure out what the big deal was, until years later when my grandfather started telling his war stories and suddenly things made more sense.


A lot of guys had a much rougher war than my grandfather. Way more direct combat. Saw stuff much worse -- and had to DO things that were hard to live with. I think the psychological fallout of stuff like that explains the vast majority of "shell shock", without the addition of CTE-like physical head trauma. I'd wager that when the docs said Stewart's father's shell shock was a reaction to aerial bombardment, that was really just a face-saving measure to try to explain away the perceived "weakness" of his condition.

newtboy said:

I feel there's confusion here.
The term "shell shock" covers two different things.
One is purely psychological, trauma over seeing things your brain can't handle. This is what most people think of when they hear the term.
Two is physical, and is CTE like football players get, caused by pressure waves from nearby explosions bouncing their brains inside their skulls. It sounds like this is what Stewart's father had, as it causes violent tendencies, confusion, and uncontrollable anger.

Bad driver gets 'accidentally' PIT-ed

Khufu says...

yup, he hit the brakes as soon as he noticed the guy wasn't going to shoulder check... Maybe he could have hit the brakes harder and sooner, but why would you assume the guy wouldn't look? to brake that hard when the other car was still in it's lane would have made no sense and been more dangerous in the conditions.. this guy with the dash cam did nothing wrong.

also in Canada we can have partial fault in accidents too. % of fault allocated and dispersion of insurance follows suit. so on a bicycle, you can be found partially at fault if you got hit, but since there isn't insurance for bicycles, only the driver's insurance would have to dish out.

jmd said:

Except that you CLEARLY see after heavily accelerating to pass 2 cars he hits his brakes and slows down when the other guys blinker goes on.

BSR (Member Profile)

Those are some good drugs

newtboy says...

What drugs do these people get?
I rode my bicycle home after getting my wisdom teeth out, and drove home after root canals. I've never been offered the good stuff...I feel ripped off.

Near Miss

newtboy says...

But bikes can brake much faster due to being 1/10 the weight. My bicycle has far less contact and stops on a dime.
I'm pretty sure some new bikes have abs too.

Khufu said:

Well as for the braking, bikes actually can't break as fast as a car often due to very tiny tire contact patches... breaking hard on a bike can be quite dangerous! My car can stop WAY faster than any motorcycle I've owned because with the car you can just slam on the brake and abs kicks in. and tons of tire contact. Also this is probably a go-pro or similar, so wide lens and everything looks way further than it would have appeared to the rider.

4 Revolutionary Riddles Resolved!

newtboy says...

Calling him out on #1, he asked "what is this Object (in the cylinder)?". Honey and ping pong balls are not a single object.

Also the bicycle question, you need a rear sprocket about twice the size (or larger) of the front one to negate the wheel/crank ratio. Only custom bikes made for this question would have that gearing...so technically he's right but no one will have those results. (Edit:with the possible exception of Krusty, because his crank may be larger than his tiny wheel)

4 Revolutionary Riddles

newtboy says...

3) it moves backwards because the force is applied to the entire system/bicycle. The wheel going backwards turns the gears and chain, rotating the pedal 'forwards' (rotating it in reverse). Because the wheel is much larger it travels much farther back than the pedal rotates forwards, even with 1:1 gearing the pedal actually travels backwards slightly compared to the ground, but in higher gears it gets much easier.
It's because the tire is so much larger than the crank, that makes it easier to rotate the tire than the crank even at 1:1, so it goes backwards.
It's counter intuitive, but I actually checked my work and yep, my bike went backwards in all gears....no sliding needed. Try it.

visionep said:

I guess the hint for these is the rotational test that they show at the first.

1) A sticky object that would let go like a wall crawler that climbs down a wall would create this effect. (see below)
2) You can't. As you approach infinite speed it would get very close. (see below)
3) The bike will move forward. (see below)
4) The outside parts of the wheels that overlap the rail. Also if the train has a flywheel that is larger than the wheel size the bottom of the flywheel would also always move backwards faster than the train was moving.

1) He says "what object is inside?" so I'm not sure a liquid would count. Also a viscous liquid would flow a slow rate and would probably not stop and start. You might be able to get a viscous liquid to stop and start if you had fins, but that still might just move slowly or gain enough momentum to roll fast without any flow.

2) A little excel calculation shows that the average velocity approaches twice the initial but will never hit it.

attempted m/s - total time - average m/s
1 100 1
2 50 1.333333333
3 33.33333333 1.5
...
200 0.5 1.990049751
201 0.497512438 1.99009901

3) I'm not sure if the parameters of this experiment are explained sufficiently.

If it is allowed to slip then no matter the mechanical advantage a hard pull should always be able to get the bike to skid back and defeat friction.

If the bike is not allowed to slip on the ground then I don't understand how it could ever move backwards, the only options would be that it doesn't move at all or it moves forward.

If it can't slip then the ratio of the pedal to the wheel is what is in question. Bikes only have gear ratios higher than 1 and the crank is smaller than the tire so the tire will always rotate more than the crank thus the bike should move forward.



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