41 points
*

So itโ€™s best to always be the last pedestrian in the line. OK, got it.

permalink
report
reply
22 points
*

Last time I heard about it it was 50-60% fatality at 50km/h, but only 3% at 30km/h.

Maybe depends on which country the data comes from.

Anyway, 30km/h in the city is a given.

permalink
report
reply
24 points

Also gonna depend on the car. The oversized lifted truck is gonna kill more reliably than a mid sized sedan

permalink
report
parent
reply
1 point

I think the info was from sweden, maybe volvos are more cushiony :-)

permalink
report
parent
reply

The country also factors into it because inertia depends on weight and increases exponentially by speed so if there are more trucks and SUVs, that rate goes up rapidly. The average car size also increases YOY, so itโ€™s continually getting more fatal to be hit by a car.

permalink
report
parent
reply
15 points

What version of the trolley problem is this

permalink
report
reply
5 points
*

Two tracks, one with 50 people tied where the switch is currently set, and the other with somewhere between 0 and 5 people tied. You could switch the trolley to the other trackโ€ฆ

โ€ฆbut the trolley passengers would be upset at you because theyโ€™d be 4 minutes later to work every day. Oh no.

permalink
report
parent
reply
12 points

30 km/h is 8.3 m/s, are you implying the driver reaction time is 2.5s? Or is this chart for mentally challenged drivers?

permalink
report
reply
3 points

Iโ€™m trying to figure this out too. Those distances seem really suspicious. At 30km/h, Iโ€™m pretty sure I can stop my (admittedly small) car in less than 1 car length. Maybe half a car length, something like 2m? Way less than 9m.

permalink
report
parent
reply
2 points

And looking at 60km/h, thatโ€™s 17m/s and they are claiming a 43m stopping distance. That would be like hitting the breaks and your car just slides on the pavement for 2.5 seconds, traveling the distance of an Olympic swimming pool, before stopping. Thatโ€™s only reasonable in the worst possible driving conditions. Or maybe with an enormous and heavily loaded vehicle?

Or maybe Iโ€™m being too optimistic here? Maybe these are numbers from actual accidents and in real life people hit the break slowly at first and stuff like that?

permalink
report
parent
reply

Sure, if someone says 3-2-1 brake and youโ€™re expecting a test. But thatโ€™s now how people react while driving every day.

permalink
report
parent
reply
2 points

I get that my performance will change depending on whether Iโ€™m expecting a test or not. But I think if my car has its breaks slammed, itโ€™s going to stop in less than 9m starting at 30km/h, regardless of whether itโ€™s expecting it or not. Itโ€™s the stopping distance that Iโ€™m feeling is larger than it should be.

A couple questions. Is the stopping distance in this diagram the distance the car travels after the driver has completed their reaction time and started hitting the breaks? And where does the value from this distance come from?

I wouldnโ€™t have thought to ask you before. A lot of times people just post things they find online that impact them in some way. But you seem to have a lot of knowledge that goes beyond just seeing this image.

And, anecdotally, I was driving late last night and an animal jumped out into the road ahead of me. I would like to avoid hitting an animal just as much as hitting a person. But I didnโ€™t immediately slam on my breaks to stop the car as quickly as possible. I gradually squeezed that break pedal until I was rapidly slowing. So maybe my assumption about stopping distance is wrong. Maybe the car can stop faster, but when driven by average people it doesnโ€™t, simply because average drivers donโ€™t stop optimally.

permalink
report
parent
reply

Yep. 2.5s is the average perception reaction time. This includes

  • Perceiving the person
  • Understanding the situation and thinking about whether you need to stop
  • Moving your foot to the brake pedal

Keep in mind, most people feel comfortable driving and not expecting to have to make an emergency stop at all times. Sure, youโ€™d be ninja-fast if you were in some test environment where you expected the hazard and were trigger happy on the brake but thatโ€™s not the real world.

A few US states, including California, have adopted a standard driver reaction time of 2.5 seconds. The United Kingdomโ€™s Highway Code and the Association of Chief Police Officers ACPO Code of Practice for Operational Use of Road Policing Enforcement Technology use 3.0 seconds for driver reaction time.

permalink
report
parent
reply
5 points

Whats this in Freedom Units?

permalink
report
reply
18 points
*

You got hit by an emotional support vehicle F-9000, youโ€™re dead at any speed

permalink
report
parent
reply
2 points

100kph is 60mph so 50 is 30, 25 is 15 etc

permalink
report
parent
reply

Fuck Cars

!fuckcars@lemmy.ca

Create post

Your hub for collection of materials that contribute to a world with less car ownership. Including buses, motorcycles, bicycles, skateboards, longboards, scooters, hoverboards, e-scooters, pedestrians, walking, running

Community can decide if: truck have a place here.

Matrix

Discord

Community stats

  • 340

    Monthly active users

  • 133

    Posts

  • 607

    Comments