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I know those answers I think. I'll go with, Longer than you've been a cop for and investigated more.

Just a guess though.

   

Just a guess, you're probably right. I'd like to see someone in his position start backing up the arguments instead of parroting the traditional narrative. I'm inclined to agree with the video authors positions, but he did a right-up job making that one officer look like a fool. Frankly that wasn't cool.

It would be nice to see a well thought out counter argument from someone in a similar position to that officer. I like to know the "why"s from both sides of an argument so I can make an informed decision. Eyebrock is using physics as his meathodology. I'm game, let's use physics. If he can support his position with real world examples, even better.

   

As he said, Bullocks. A 110km/h to 0 decelleration in 2 seconds is called a 'crash' and it exceeds the crash testing done on vehicles (30mph!!). The only cars capable of doing that kind of decelleration safely are not allowed on public roads. So, a lot of energy is transmitted to occupants in such collisions, and that results in injury and death.



http://www.nhtsa.gov/cars/rules/import/FMVSS/

   

... a.k.a. "SPLAT!"

   

Most of those standards aren't applicable because the likelyhood of a head-on collision or a t-bone at 110kph on an expressway like the #1 through Vancouver, the Coquahalla, or the 19 are incredibly low. I would like to see testing of vehicle rollovers at expressway speeds made a standard part of safety testing.

Now on to your statements, absolutely it is a crash. Let's play with your speed of 110kph, and my de-acceleration time of 2 seconds. The speed translates to 30.5556m/s. In order to go from 110kph to 0 in 2 seconds, you would have to lose 15.27778m/s per second. To calculate the G-forces, you put whatever the speed is over the acceleration you'd experience in free-fall at 1g, which is 9.83m/s^2

In our case 15.27778/9.83 is 1.5541994. Lets round up and call it 1.6g average. That's not a heck of a lot, certainly not

This kind of accident would occur if someone doesn't shoulder check before a lane change, and they either end up getting rear-ended or doing a pit-manuever on themselves. Both vehicles collide at relatively the same speed, and both go spinning out of control. Best case scenario is each vehicle has some fender/bumper damage and needs a new set of tires. Might also need to get the shit-stains in the seats detailed.

What would probably happen is one or both roll (hence why I want this to become a part of safety testing), either on the road or into the ditch. But modern vehicles are designed for such a scenario (roofs don't cave in, glass doesn't turn into shards), and if the occupants are properly buckled up they should come away from the accident with minor to moderate injuries, but very much alive and able to walk again. Again the G forces experienced would be minor. Probably higher that the 1.6g I cited, but certainly not the sustained 40g or peak 100g required to kill someone.

There is also the off-change that upon entering the ditch you strike a more solid object... Say the back of a tractor-trailer unit, a tree, a bridge, or go off the edge of a cliff. Well whether you are doing 50 or 110 when the accident occurs, in any of those situations you are very likely fucked up if not killed. This is called a "freak accident" and while they do occur, they certainly aren't the norm. They are an accepted risk of driving, and if you aren't prepared to take the risk of dying when you drive, either drive at the speed you feel safe in the appropriate lane, or don't drive at all.

   

If you notice, the speeds tested are double those for vehicles on a highway. It applies because all vehicled in Canada must meet these standards, and the impacts are tested on fixed objects, not with moving objects. A head on collision would quadruple the speeds involved, and the forces would be exponentially greater.



It takes a person tripping and falling to cause a basal skull fracture that would kill you instantally with only 500N of force. Many times less than a 110km/h collision.

This crash killed Dale Earnhart fron just such a fracture, and yet the accident was far less severe than many he had walked away from.

https://www.youtube.com/watch?v=rXGKys62TXw

And your calculations don't take into account things like stopping distance and force increases when someone is driving only 10 km/h over the speed limit.

Speed kills. To quote Chief Scott "Ya canna change the laws of Physics!".

   

How many Newtons are there in a metric Splat, again?

   

Double those on a highway would be 220kph.

You are flat out wrong about the head on collision bit, which is fine. Many people get it wrong. I'd explain the science behind it, but Myth Busters tested it, and the video says it all. I invite you to watch.





You're correct, a head impact can kill with very little force. But that is the skull impacting something. In a collision, when you are properly restrained, your skull shouldn't be hitting anything but the airbag. It isn't going to magically shatter from the force of the crash. It needs to hit something.

The crash that killed Dale Earnhart fits into the freak accident category. As I recall it was a seatbelt malfunction that killed him during an accident which he should have walked away from.

I was calculating for time, not for stopping distance. If it takes you two seconds to stop it takes you 2 seconds to stop. Although conveniently at 2 seconds of acceleration the distances would be the same as the meters measured in the velocity. In the case of 110kph you would stop in 30.6 meters over 2 seconds at a de-acceleration of 15.3m/s^2.

The math is the same for 120kph. Instead you are now travelling at 33.334 m/s. To slow down over 2 seconds would require a de-acceleration of 16.667m/s^2. This in turn would produce 1.7g of force. A change of 0.1 g over the vehicle which de-accelerated from 110kph. It would also take you an extra 3 meters to stop.

   

Imagine if ... the science fiction "warp bubble" around a spacecraft were possible. Aside from the EXTREME ionizing radiation around such a phenomenon (think: "Crispy Critters"), imagine what the sudden acceleration would do to our gelatinous bodies?

   

Good question. I honestly don't know. If I had to guess I'd imagine it would be similar to what LSD is currently doing to your brain.

   

A Basal skull fracture is where your spine tears away from the skull, severing your spine from your brain. Death is instant.

That is exaclty what happened to Mr. Earnhardt. It was a relatively minor crash, but all the force made his head keep moving forward but the seatbelts restrained his body and *pop*. Even at the time, everyone else wore a Hans device, which prevents this kind of injury and is manditory in all motor sports now. Back then, it was optional and #3 was a staunch detractor of the Hans device which would have saved his life.



Now, assume you aren't crashing (worst case), but reacting to an accident and braking. Reaction time of .5s means you cover 15.3 meters or 5 car lengths before you even react. A quarter of your distance is already shot! On a dry road with a coefficent of friction of .8, the average car will stop in 58m. Total distance - 73m.



Again, let's assume accident avoidance. At 120km/h the reaction distance is 17m, the braking distance is 69m and the total distance 86m, or in other words you didn't avoid braking for the accident, but have become part of it.

And we aren't even talking here about what happens when you speed on roads that were designed to only accommodate vehicles of a given speed. Fatal concequences can happen just because of a bump in the road that you wouldn't even feel at the speed limit.

Speed kills.

   

I did not know that. What kind of force is required to cause that to happen?



I was doing my math for a collision already occuring. I did not realise you were bringing reaction time into the picture. If that's the case, keeping the vehicles as close together in speed as possible is more important than the speed itself. Someone doing the speed limit will have less time to react to someone going 20 below the speed limit (closing speed of 20kph) than someone doing 10kph over the limit will have approaching someone doing the limit (closing speed of 10kph).

   

The other aspect of higher speeds is entering and exiting from the road. Many on and off ramps are already too short for what I'd call safe driving, and I drive a some what over powered sports car.

Heavy trucks are now sometimes more or less forced to just merge into traffic and hope people move, adding another 50km to the top speed is just going to cause more people smashing into the rear bumpers of trucks, or see the truck too late and freak out, over correct and flip their rides.

~

The idea that we can just raise the speeds also ignores traffic. Take a busy highway, if you ramp up the speed most people will not follow at a safe distance, but will default to their city driving distance. Have anything cause a slow down and in heavy traffic you get the worm followed by stopped or almost stopped traffic, with cars closing in on them at +160km/h.

~

If you want to save lives raising the speed limit isn't a good solution. May other changes to the physical size, shape and configuration of a road would save far more lives. Although cost a lot more than putting up new signs.

   

I agree with this.

the 400 and 401 series should be at 110, but the 407 is an express why not make that limit 120. Up here hwy 11 reduces to 90.

   

This I can agree with. As it is many interchanges in the lower mainland have too short of enter-exit lanes for the current speeds. I think that is why people are suggesting no more than 110 until you get past Hope. The interchanges on the 5 between Hope and Kamloops, and on the 19 between Parksville and Campbell River (except for the two stoplights, points to follow) are capable of supporting speeds up to 130.

Note on the two stoplights on the 19, they really should be upgraded before increasing the speed on the Inland Island Highway. A bump to 120 they could probably handle keeping the speed step-downs to 90 where the lights are, but as it is so many people hit cruise control at 130 and ignore those zones. They WILL need enforcement. I'd rather see them set the limit to what people usually drive at, 130, and put the interchanges in as was originally promised. I don't know about the Cape Horn stoplight, but the Fanny Bay light can get fucking busy.



if you raise the limits to 120 or 130, why the fuck would anyone in their right mind be going at 160? I say in their right mind because I know there are retards out there. but even if the limit was 80 they wouldn't care. Further, usually when the worm syndrome is occurring people are travelling below the posted limit before they come to stopped traffic.




I hope both safer interchanges and increased speed limits will occur.

   

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