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Damn. I didn’t realize it was so drastic. 100% fatality rate seems crazy, even rounded
Good thing we went from 60 to 50 km/h speed limit in the cities. We should go even lower!
Some Italian cities (like Bologna) already have adopted 30km/h speed limit in 70% of the streets
I remember a public safety ad being shown that showed the difference in either 30 and 35mph or 30 and 40mph. Was quite dramatic.
This one was quite widespread in UK TV, it was one of the first government films to use such shocking imagery and dark themes, 40mph vs 30mph. it’s probably a bit mild by today’s standards, but it was notorious at the time…
That’s the one. I also seem to remember a version where it showed the car with locked up brakes and where it would have stopped, on a street in a town/city.
Edit; Found it.
Local news:
“The officer spotted a grey BMW going 87 MPH in a 40 MPH zone”
For our European friends:
87 MPH = 140 KPH
40 MPH = 64.4 KPHWhy Europe? Most of the world uses KM/H.
Yea I’m here a short distance from the border of the US and need a translation too.
Oh neat, I’m one of the green people in the first two rows. Not 100% sure how fast they were going, somewhere in that range. Just glad it was a short sedan and not a big truck/SUV. I live in the US, could’ve easily been a truck and ran over me instead of me toppling onto the hood.
crap. I hope you’re ok now buddy
Thanks :) I got incredibly lucky and walked away with only 3 bruises and a couple scrapes.
Kinetic energy = mass*velocity^2 in action. Faster you go the harder you stop.
This needs to be updated.
Getting hit by a pickup truck at 30 MPH is similar to getting hit by a Honda Civic at 120 MPH for kinetic energy.
That’s besides the fact that pickups have a much taller hood vs sedans so there are significantly higher rates of head injury.
Taller cars and trucks are more dangerous for pedestrians, according to crash data
You’d have to be very unlucky to get hit ffrom both side at the same time though
So my curved front sports car is totally safe to ram into pedestrians with?
/S
I’d rather be hit by that at 20 MPH instead of a full duty lifted pickup with a fresh shiny paint job on chrome wheels (mall crawlers)
I don’t think pickup trucks should be banned. They should be commercial use only. It’s not a family car or a daily driver.
Fuck mall crawlers
And then there is the SUV class. Aka the non-passenger work vehicle family passenger vehicle.
So they passed laws for emissions and fuel efficiency of passenger vehicles to help with pollution.
These laws force MPG ratings on sedans and SUVs. But they’re looser for trucks. Car manufacturers realized its also looser since its calculated by weight.
So these fuckers decide to build SUVs on pickup truck frames and make pickups even bigger so they don’t have to tighten up the fuel efficiency…
This is one of the main reasons there are so many bigger class vehicles being made now.
Add in all the new LED headlights. Which are too bright because the regulations are outdated based on wattage instead of lumens.
So you have taller vehicles with brighter headlights blinding everyone.
I’m at the point where I’m aiming for a SUV instead of a sedan for my next car…
If you dudes want to start over, feel free to copy our regulations. It would also allow you to sell cars here. LED headlights are great, given they keep to regulations.
Best, an European.
I am not sure why the difference in energy related to vehicle mass is relevant here as humans have an insignificant amount of mass compared to either vehicle, so transferred energy should be roughly the same. However, the difference in how the collision plays out (pulled under Vs thrown above) should be a huge impact
should be a huge impact
I see what you did there.
The higher mass and force transmitted by a truck means the human will be thrown further and possible impact other objects at a higher speed
Not all of that energy is transferred. The car doesn’t stop as if it hit a wall. Usually it barely slows down. The human on the other hand gains at most the kinetic energy corresponding to their body mass and the speed of a human bouncing forward off the car at around the same speed as the car was going, so a tiny fraction. Of course impact geometry will determine the specifics and pickups suck there too. The important thing about kinetic energy is that it’s dependant on the square of the velocity. That’s why speed kills. The mass is just a linear relation.
The issue is energy transfer doesn’t care about weight of the human, more kinetic energy will impart more speed to the human during the impact impulse. Imagine a solid bowling ball hitting a beach ball vs a plastic hollow bowling ball hitting a beach ball
You are thinking of perfectly elastic collisions. That’s a fantasy and not applicable to the real world. A human body isn’t a beach ball and cars have crumple zones (although I believe pickups suck in this regard as well).
And your comparison isn’t applicable in terms of masses either. Both a sedan and a pickup are way heavier than a person.
Car crumple zones are tuned to prevent damage to the car, not to pedestrians. If they were they would have airbags on the front of the car. A car can kill a pedestrian by hitting them with a crumple zone, without that zone crumpling.
This means most of the non-elasticity is in the pedestrian’s body; how they flop onto the hood of a normal car, and how their bones crumple and flesh splatters before their brain and vital organs do.
Of course if a car hits a pedestrian hard enough, the crumple zone will crumple to reduce damage to the car, but that’s overkill as far as the pedestrian’s life is concerned.
That said, if you (unrealistically) assume the speed at impact and the geometry of the hood are the same, the difference between a car that weighs 20 times what a person does and one that weighs 40 times that is (40/41 - 20/21), or only about 2.5%.
Realistically, the weight increases the braking distance and the hood geometry makes the pedestrian’s body perish more elastically.
Well, yeah. I can kick a dent into a car, but mostly I just raised crumple zones to emphasize that these are inelastic collisions we’re talking about.
And yes, the breaking distance is pretty much the only way that vehicle mass is relevant for pedestrian survival.
more kinetic energy will impart more speed to the human during the impact impulse.
Partially correct, the speed (technically acceleration) of the human after a collision is limited by the decceleration of the moving object caused by thr human. Since a car and a truck decellerate about the same amount when receiving the counter-acceleration of the human, the force transfer remains similar.
The bowling ball will not slow down in the slightest when is hits the beach ball, accelerating the beach ball up to it’s speed.
The plastic ball will lose significant speed hitting the beach ball, decelerating itself significantly as it accelerates the beach ball.
I’m going to pick some easy math speeds/masses for demonstration. 2,000 kg sedan, 4,000 kg pickup and 100 kg human. Starting velocities of 20m/s and 0m/s. An impact/acceleration time of 1s.
The sedan hits a pedestrian with (f=ma) of 40kN. It takes 2kN to bring the human up to 20 m/s. So the sedan will be somewhere around 38kN, or 19m/s at the end of it and the human absorbing 1.8-2kN.
The truck has f=80kN. Same 2kN for the human. So the truck will be somewhere around 78kN or 19.5m/s at the end. With the human absorbing 1.9-2kN
In either case the we talking a difference of 1.8-2kN for the human. Regardless the mass (and total force) of the vehicle, the relatively small human as a maximum force they can absorb. And that maximum force is heavily related to the speed of the larger object.
Not to say trucks/SUVs aren’t deadly for other reasons (like where and how the force os transferred)
I think the point is that it’s not a linear scale when comparing energy of the vehicle to energy transferred during impact. It flattens out drastically at higher vehicle masses, and the value of the energy becomes a false or skewed argument against heavier cars.
Your math is wrong. Kinetic energy scales linearly with mass, quadratically with speed. The graphic you included supports the idea that at same speed, the pickup truck has double the KE. The 120 mph sedan has dramatically more KE than a 30 mph pickup.
Assuming that your sedan has exactly half the mass of the pickup, it would match a 30 mph pickup’s KE at 30*sqrt(2) mph, which is somewhere between 40 and 45 mph.
I got hit by a large SUV doing between 30mph and 40mph a few years ago. I can’t tell you why or how, but I had a split second to twist and plant my hands on the hood and jump so I went up instead of under. Went into the windshield (broke it) and then got launched when she slammed on the brakes. It put my radius and ulna into my hands, my back into my guts, and knocked my brain so hard I gave the emergency crew a phone number that belonged to a girlfriend I’d broken up with almost 20yrs prior. Took me a year to be able to write again, not just physically. I’d start putting words to paper and end up with gibberish because between my brain and my hand it didn’t connect. Had to leave post-it notes around the house as a check list- did you eat, bathe, brush your teeth, feed the dogs, piss? My ability to sleep was wrecked, no circadian rythym. I don’t entirely believe in fate, but how the fuck that didn’t kill or cripple me boggles my mind (what’s left of it) daily.
That’s horrible. I can’t imagine going through that.
Glad you’re alive. Thank you for sharing.
The energy difference is only really relevant if the thing you’re hitting is significantly heavier or at least similarly heavy like a house or another car. For a person it’s still much worse, but that is moreso because of the high hood of the car.
I know pickup trucks are heavy, but I’m surprised they are 16 times heavier than a Honda civic. The more you learn.
Well… the person in the last photo looks like they’re not happy about getting hit by a moving vehicle at all.
If we’re going for efficiency, I think getting hit by both cars is the right move.
K = 1/2*m*v^2
There’s quite a large discrepancy between this image and OPs image. This image says the survival rate of 30 mph (48 kph) is 60%, while OP’s image says 50 kph it’s at 20%. I wish they included a source for the data that could explain it.
This is the same issue I take with braking distance scales. They often vary wildly, and some don’t even follow a quadratic increase in distance like you’d expect.
We wouldn’t have so much trouble with this if all men had the same size dick.
We wouldn’t have so much trouble with this if all men had the same
size dickupbringing that leads to the sort of maturity that leads people to be not shit.Let’s not bring body shaming into this mmkay?
Its not body shaming, its overcompensation shaming.
They’d just lie about it anyway
Jokes on you, I don’t know kilometers
somebody posted this in the comment above yours 13 minutes before you commented ☞
I’m guilty of this when using a web browser, I’ll scroll down a page and open relevant posts into new tabs until I’ve accrued several. Sometimes I don’t get to them for quite a while so if I upvote it’s surprising how high the number jumps until I realize it’s sat there for half a day.
I try to refresh when commenting because 9/10 times someone else has already commented the same thing since the internet is dead but sometimes I forget.
So multiply by 0.62.
I believe in you, this is what all those years in grade school trained you for.
Awe, thanks. I memba grade school.
okay but don’t fuck it at any faster than 30 kph
Mass times velocity equals FUBAR…
Mass times velocity squared, that’s why the huge difference in outcome for small changes in speed
A sense of humor is terrible thing to waste…
If you think you were making a joke up there, you might not actually have a sense of humour.
Great now do SUVs for the Americans. Go ahead and assume they are not simultaneously being shot at just for the purpose of keeping the simulation simple.
I mean americans are also fatter so it must decrease the risk.
There’s a new neighbor at the end of our street with small children. She always puts one of those green children at play signs in her front yard, yet insists on driving 25-30mph down our suburban street. The rest of the neighbors hate her.
Now do light rail, trains, and busses.
don’t forget yachts and cruise ships
Those tend to be more predictable than cars in terms of where they’ll be
Roads. Cars and busses will be on roads.
Tracks. Trains and light rail will be on tracks.
I’d say both are pretty predictable.
Train and light rail only capable of moving on track, while car can be driven everywhere, even on pedestrian path. How is train and light rail as predictable as car
I have definitely heard of children being killed by a car while waiting for a bus in a bus shelter several metres away from the road
I have read about cars smashing through walls of houses
I have read about a car used to kill the children of the driver in a lake well away from the road
Cars are not guaranteed to be on roads when they are killing people
Cool how you left out trains.
There are also far fewer of them per passenger, so fewer chances for one to come by. They are also operated by professionals who can call in sick if their ability to operate the vehicle is impaired.
A bus could be ten times deadlier in a crash than a car and it would still be safer if it carries fifteen passengers. It could be a thousand times deadlier if operated by a drunk person and still be safer than cars because drunk people don’t operate the vehicle when getting home by bus.
After watching Gen V, “fuck cars” got a different connotation.
But just wait for the deafening screaming of people when 30km/h limits are enacted in front of schools because that would dramatically reduce lethality of accidents, while costing car drivers maybe a few seconds of drive time, if at all. It is quite a spectacle.
I live near an intersection. Drivers will ten second horn blast because someone won’t crawl up the arse of the car in front of them just so horatio can mount the kerb and get into a sliplane they can’t exit until the lights change anyway
So what i’m saying is you’re underselling the stupidity
How dare they put an authoritarian surveillance system (speed camera) near the school. This is an unfair tax on normal people. Its not about safety, it is about control. - most of my city until the province outlawed speed cameras entirely.
In all seriousness, paint doesn’t enforce speed. What you need is to rebuild streets for that speed. Have a look at the Netherlands for reference. You need pretty little enforcement when streets are built for 30 km/h. Narrow, priority pumps at crossings for pedestrians, where your car seat is punch through your pelvis if you go anything faster than 30 km/h …)
You are right, but there were also several studies done that proved the speed cameras lowered speeda significantly, even after the camera had been relocated.
Lets not let perfect be the enemy of good. Those cameras reduced speeds and generated revenue for the city that was specifically dedicated to making streets safer, including bollards, lane narrowing and speed humps. The removal of the cameras both made the streets more dangerous, and cut funding for real safety improvements. All because speeders were getting caught speeding and considered that unfair.
Sure. But if roads are built for the speed, the road enforces the speed. If driving faster will shake you so badly that it feels like an accident, most people won’t do it. Also making streets narrow, with tight road crossings and curves, and subjectively more dangerous to the car drivers, actually makes streets safer, especially for people outside of cars.
Of course that is not possible everywhere and then speeding controls, including cameras are the next best thing.
We can’t just update the roads for free. The cameras were a big part of the plan to make the roads safer.
Man I’d hate to be one of the 40 subjects of this experiment
Spoiler
/s if that wasnt obvious
- don’t forget the driver. He’s in no danger but comes out with serious ptsd
Depends on the driver. Also, I think Teslas “FSD” cars are a perfect candidate. Or, hell, Musk would probably do it himself, just for the fun of it.
The worst part is even if you survive they paint you all green
