What Makes A Collision Lethal? | Neil deGrasse Tyson Explains...

What’s the safest car accident? On this explainer, Neil deGrasse Tyson and comic co-host Chuck Nice explain the physics of high impact collisions, kinetic energy, and how to keep yourself safe in a car wreck.
We dive into transferring kinetic energy and the physics of a moving vehicle. What is a crumple zone and how can they save your life? Learn about the physics of how seatbeats save you and why wearing them even when the car is going slow is still important. Can a long car crash actually be better? We discuss the point of airbags, internal damage the body might endure, and absorbing kinetic energy. We take a look at surviving high impact collisions… it’s not a miracle, it’s physics!
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Science meets pop culture on StarTalk! Astrophysicist & Hayden Planetarium director Neil deGrasse Tyson, his comic co-hosts, guest celebrities & scientists discuss astronomy, physics, and everything else about life in the universe. Keep Looking Up!
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[@GovindSomai]

"It's a miracle!" "No it's not... It's physics!" Probably the best thing I've heard in a while.

[@prettycountrygirl2]

Yes, that's a good one.

[@alexy.9306]

Read that when he said it. Why does this happen so much? Wierd

[@vykintasmorkvenas6839]

You can see it everywhere: people are the more inclined to believe in miracles the less physics they know.

[@tedgey4286]

Don't thank the physicists thank the engineers

[@justdoit83388]

If you don't believe in miracles they'll never happen to you. And believe me, because we live in a world with humans - who make mistakes in every aspect of life regardless of skill - you'll always be that more doubtful of change and that more begging for one when it really affects you. Peace ✌️

[@BrianHartman]

This reminds me of last year, when I got hit by a car. I'm in a wheelchair (and I was before the accident, just to be clear) and the driver hit my chair probably going somewhere between 15-20 MPH. I was launched out of my chair on to the ground and spent some time in the hospital. But what reminds me of this is the way my back wheels were bent at a 90-degree angle from where I was hit. That's an enormous amount of force that didn't end up going into me directly.

[@JP-xd6fm]

People don't realize how much damage can cause with a car even going "slow". Yesterday I saw a 9 or 10 year old girl being almos hit by a car in a parking lot, she was going to cross running and at the very last moment she stoped, the car didn't stop or brake, for sure even see her. The car was speeding at 25 or 30 in a place that is only 15

[@justcallmesomething8089]

Your lack of walking ability likely saved you, I think moments like these are why some believe in a God.

[@th_js]

@@justcallmesomething8089 What the heck does religion have to do with coincidences and physics?

[@SpyroTek]

@@th_js Maybe they’re thinking God likes to cause accidents.

[@jeffdavis5723]

*WHY DO PEOPLE THINK THAT A IMAGINARY BEING HAS ANYTHING TO DO WITH THESE THINGS⁉️* 😳

[@nikkehautapelto1323]

This reminds me of the Jeremy Clarkson quote: "Speed has never killed anyone. Suddenly becoming stationary, that's what gets you.”

[@gnarthdarkanen7464]

Too much acceleration, positive or negative, will get you, though. (just to be clear)... Humans can generally take about 9 or 10-ish G's, some astronauts and pilots train enough to manage 11, but beyond that is hospital worthy if not outright lethal, whether your speeding up too fast (like being hit by a moving car) or slowing down to fast (like hitting a wall)... If I recall correctly, the "official" lethal limit is 15 G's... BUT they may have updated since my last reading, too... so... worth looking up to confirm... AND yes, acceleration is measured in G's relative to 1 Earth Gravity = 1G (also for clarity). ;o)

[@wayando]

Same way jumping with a rope around your neck has no effect ... Until you stop suddenly.

[@calabrais]

@@gnarthdarkanen7464 This is true, however since we're being pedantic the quote says "speed" not "acceleration". Cheers.

[@gnarthdarkanen7464]

@@calabrais AND I'm only being pedantic enough to point out Clarkson is only half right... ;o)

[@jpdemer5]

As the guy falling past the 40th floor said, "So far, so good."

[@LEDewey_MD]

Having a car "designed to crumple in a controlled fashion" probably saved me. Driving my Ford Fiesta at 65mph on I-94 in Detroit, a PARKED van suddenly appears in my (middle) lane with no where for me to go, (cars on both sides) Woke up 4 hours later in Detroit Receiving hospital - very banged up - my chest cracked my steering wheel, severe concussion and whiplash - but still alive. Made a full recovery a few months later..

[@pewpewdragon4483]

Am I interpreting you wrong or... Did your steering wheel make a full recovery though..? 😅😂

[@xPoN3dx]

As a mechanic who has played with airbags. They are not soft what so ever. They catch you like a wall for a few moments then as the expanding gasses hit peak it then slowly evacuates the bag. Then it becomes soft. It's generally there to prevent whiplash as your neck trys to snap forward. Holding you still, attaching you more to the vehicle as the vehicle absorbs the motion via crumple zones. Also they fill at somewhere around 100mph to 250mph. Otherwise fantastic show, have been a big fan for years. Also have the ballpark numbers behind the math of a crash if you ever want them. Edit, bad wording on my part, reworded to better describe what I ment. Will re edit again if better information is provided.

[@deltashevy]

The purpose of the airbag is to hit it as it deflates. This is why is important your position in the chair and the distance between your body and the weel. Your hands should be at 9&3 and not 10-10, the angle of your arms should be 95,100. Also, when you push the brake padal to maximum you leg should have an angle of 120, never straight. Your headrest should touch almost like the crown of your head

[@JaguarBST]

Aren’t they much softer than the steering wheel or the wind screen?

[@StarTalk]

Fascinating, thank you for explaining!

[@inevespace]

​@@JaguarBST how are you going to hit steering wheel or windshield when belted? Airbags are useless without belts. And as I know they give very small gain in survival and injury rate in accident statistics. This is why we don't use them in autosport. Risks related with them are higher than gain in safety for such application. It does not mean we shouldn't use them on road cars. But people underestimate importance of belts and overestimate importance of airbags.

[@jpdemer5]

@@inevespace Tell that to your neck if you ever crash with a belt only, or get T-boned ... the bag will protect you from serious damage. Racing drivers have helmets and neck protection, 5-point harnesses, plastic windows, and specialized seats, which is why airbags are not necessary.

[@Micloren]

Measurements I’ve seen for Usain Bolts top speed are between 27-28 MPH.

[@zackfruchter7832]

Wow Neil. Thanks a lot for this explainer. As an EMT, I arrive at car accidents every now and then. We always look at how bad the car is beat up and judge the patient based on that (as well as the patient themself, obviously) for next time I'll have what you said in mind.😀

[@kevon_shabangu]

Is that what you would call determining mechanism of injury?

[@douglasiles2024]

@@kevon_shabangu Yes, that would play a part in MOI. But also airbag deployments, compartment intrusion, use of restraints, etc, factor in to it.

[@StarTalk]

So glad this could be of value to you! You're doing important work. Thank you!

[@theduder2617]

Want to know how SERIOUS modern crash absorption is taken? I manufacture fiberglass components for 2020-2022 Corvette Stingray. If there is ANY defect in the molded part, it is discarded. If we so much as scratch a part, it is discarded. The components have a VERY SPECIFIC purpose and absolute care MUST be taken every step of the process. A scratch could potentially weaken the part, thus greatly altering crash absorption. One part in particular... if we mess it up in ANY WAY, it costs us $6,000. And that is before any hardware is installed. Just the raw molded fiberglass part. Not just anyone is allowed to work on that part. You must first prove yourself capable of producing other good parts before being allowed anywhere near the machine. Apologies for not being able to divulge what part exactly, but a contract agreement is legally binding. Just know that if you buy a new Stingray, it is the end result of a ZERO TOLERANCE policy regarding mistakes. And YES! If an end customer discovers a fault in the parts we manufacture, it comes DIRECTLY back on us, with a potential write-up or two. GM does NOT mess around when it comes to a $100,000+ vehicle. And we are DIRECTLY responsible for what we ship to GM.

[@madmadjenny]

My best friend and dearheart died in Jan. She was a passenger and the driver hit a very unforgiving pole at 52 mph. The driver was not wearing a seatbelt and died within hours. My friend was wearing a seatbelt but the internal damage was too great, and she succumbed after four days in ICU. There was barely a scratch on the pole. I often think, if they had hit anything else, literally anything with some give, at least my friend may have survived. I will miss her for the rest of my days. Be careful, people. Be safe.

[@777biggs]

"The bag beats you". Yes it does lol. Damn thing busted my lip. It also tasted nothing like marshmallows.

[@yiraleeid]

I was involved in a car accident 3 years ago, 40mph frontal crash, and trust me, Airbags are far, FAAAR from being fluffy and cushioning. They are designed to absorb your kinetic energy and spread it to the bag and they do it exceptionally well, but you don't feel it like that. Those videos in slow motion of airbags deploying, they look spongeous like a pillow... No my friend, It feels like you're slamming your face into the wall as hard as you can. I'm not saying they don't work, they DO really well, I'm just saying that, what you feel crashing at 40mph and hitting your head against an airbag, is not comfortable at all, it's just less worse.

[@irenaveksler1935]

@rods growing 💚 true and you don’t get injuries

[@derekseven1647]

I come to this channel for some intelligent conversations. I need to hear something smart every once in awhile.

[@sonnylecrone8468]

All the time!!!

[@user-sc9ec6wg7m]

This is one of my pet peeves about superhero movies. You can fall from an 80 story building but as long as the hero catches you just before you hit, you'll be fine. No, if you stop abruptly, it's the same as if you hit the pavement.

[@gnarthdarkanen7464]

Yeah, don't bet on the physics degree from Hollyweird. Sooner or later "plot armor" just becomes a thing... and none of us actual humans get any of that stuff. ;o)

[@mycatrita]

or when somebody falls and catches themselves. we cannot fall and catch ourselves without it dampening our fall without obliterating our shoulders.

[@Makujah_]

Gwen wasn't fine

[@nosondre]

Or catch ‘em by the arm and fly the severed arm to safety while their body continues on it’s fatal trajectory.🤔

[@jpdemer5]

@@mycatrita Gymnasts fly around and catch themselves on the uneven bars . . . I wonder what the maximum fall would be, that you could grab something and and slow down (and/or convert your linear motion to rotation) without dislocating something. Could be something that Hollywood stunt people know about.

[@austinjames3525]

Seatbelts are a must! I lost 2 friends in accidents in 2020. Neither were wearing their seatbelts. I am convinced that the one would’ve have almost certainly survived, had she been wearing a seatbelt. She rear ended a car at 60 mph. My other friend was in a head on with another car at 60 also. It’s crazy what the car looked like afterwards. Physics explains why it looked so bad.

[@xXBenutzer235Xx]

Important thing to remember with headon collisions is, that if both cars went 60mph thats like hitting a brick wall at 120mph. Thats an insane amount of energy that needs to get dispersed in a fraction of a second.

[@jakemj03]

Yes - I lost a friend also, she wasnt wearing a seatbelt - Car rolled off the highway, she was ejected, and the car rolled over her. I've been in two vehicle rollovers and walked away from both with zero injury - one was at highway speed - I always wear my seatbelt.

[@JustinMcFly1980]

Always were seat belts. And defensive driving helps. Always looking 3 to 4 cars ahead...Great Content Love me some Star Talk.

[@d00ks]

Wear*

[@TechRyze]

Were there?

[@aymanabdelilah4281]

“Speed has never killed anyone. Suddenly becoming stationary, that's what gets you.” - Jeremy Clarkson

[@EaastonCams]

Ah ha i like that

[@akinalbayrak8265]

And what makes becoming stationary so dangerous? Speed :)

[@EaastonCams]

@@akinalbayrak8265 you didn’t get it, annoying.

[@akinalbayrak8265]

@@EaastonCams then explain maybe?

[@EaastonCams]

@@akinalbayrak8265 Dude please use your head.

[@lelerk]

Wow. My family got hit from behind by a car on the freeway going about 60 mph. We spun out of control, flipped 3 times, and landed right side up and facing the other way. Not only did we walk out of it alive and well, but miraculously we only suffered scratches from the broken windshield and minor brusies. In fact, I went to work the next day (although I was a bit sore)! This explains why. Physics is amazing!

[@jasono5178]

my friend rolled a few times on a highway while trucking and ended up surfing with a broken collaborne. He always calls it a miracle that he survived but now I call it physics.

[@RS49059]

Drove a truck off a mountain in 2009 .... Idk how many times we rolled and flipped and slammed into the ground but we were in a roll cage. Got to the bottom, unbuckled and climbed through the passenger window. Truck was TOTALED but the passenger was 100% fine and just the top of my head hurt a little but only because I'm tall enough my head hit the roof a few times. Literally the funnest (obviously terrifying) thing I've ever done and 💯💯💯💯💯 if I was guaranteed the same outcome I'd do it again in a heartbeat

[@CHEVYCAMARO4GEN]

„Speed has never killed anyone. Suddenly becoming stationary, that's what gets you.“ Jeremy Clarkson

[@douglasiles2024]

What a lot of people don't realize is that there are three "collisions" in a car accident. The first is the vehicle itself striking an object. The second is the front part of the brain striking the front of the skull, and the third is the back of the brain striking the rear of the skull. The last two are called coup and contra coup. The brain, in essence, is sitting in water (cerebro spinal fluid). Therefore it will move forward and backwards (or in some cases side to side) in an accident. This is what can cause concussions and lead to traumatic brain injuries.

[@garyfrance9048]

exactly, how did they miss that???

[@YoungGandalf2325]

I was just watching another video with NDT when this one was posted. This guy is everywhere! 🤩

[@chuffmeister1130]

It's not the speed, it's the sudden stop at the end that kills.

[@jiversteve]

Coming to a halt in an uncontrolled manner?

[@chuffmeister1130]

@@jiversteve yeah, like going head first into a tree or a wall. No matter what speed you're travelling at, you're alive, until the very moment you actually make contact!

[@michaelccopelandsr7120]

@@chuffmeister1130 you're alive until the very moment you're not.

[@travismalinich1954]

I have been a collision technician for almost 12 years. I regularly hear from people "old cars were so much safer because they don't fold up like these new ones." I have tried countless ways to explain the transfer of energy during a crash, but I have settle on this. A pillow is soft, and easily fold up, right? Stand there with your hands at your side and fall forward flat on your face. Now do the same thing holding a pillow to your chest. Which one hurt more???

[@jacksonbruns9429]

Can confirm. Rolled my car 4 times walked away with a bruise. If I rolled once… would have died. Or no seatbelt I’m definitely dead.

[@dearcath]

Roll once -> dead Roll once more -> Alive If you told this to a random guy, he'd have no idea what this means when it actually means a lot.

[@roza9428]

It's not the speed that kills you, it's the sudden stop.

[@chillskeleton6529]

The safety crash testings was like 4k pounds and 31mph. Now it's being raised to 4,900 pounds and 39 mph and raised higher up. The new wave of cars is going to have to be increasingly built like air craft.

[@davidacosta9158]

I’m curious, what do you mean when you say “the safety crash”, when it is never going to hurt you?

[@epicon6]

A HANS Device is one of the biggest safety innovations that every motorsports category uses that keeps your helmet and neck in place. If that was invented earlier most deaths in racing could have been prevented.

[@dougwalker4944]

i was watching the race that killed Dale Sr. the HANS was mandatory kit after that.

[@Sajatzsiraf]

what I never understood - why it took so long for car manufacturers to realize basic facts of life and physics, and start building cars that are actually designed to actually protect us sitting in them. the bare basics are super simple.

[@afconnelly]

They will make it 8x more dangerous if it’s 4x as pretty and makes 2x the profit.

[@randyb359]

Money.

[@DimitarStanev]

@@afconnelly it’s all a compromise. You can certainly make cars safer but that would hurt aesthetics, practicality, cost, efficiency etc And people don’t buy cars based only on NCAP scores. Crumple zones have been in development since the 1950s, it’s not only about understanding physics, but certainly a better understanding of material science and construction has made them possible. In the end it has to not cost a ton and be mass produced,

[@akinalbayrak8265]

Neil’s Usain Bolt at full speed hitting a brick wall comparison is faulty. Even when you are driving 30 miles an hour and crash somewhere, there is still some crumpling taking place which absorbs the energy before your body. In the Usain Bolt example, all energy is transferred to the body without any loss since brick wall doesn’t flex. So no, not wearing a belt going 30 miles is not the same as Usain hitting a brick wall.

[@Nefville]

The best car safety system I've ever seen was in Demolition Man. They crashed and the entire inside of the car was filled with foam. Awesome idea, also would protect from glass, objects and things like that. Cleaning bill would be a nightmare though.

[@Rob-eg8qc]

Them good old Duke boys know a thing or too about physics, when jumping the General Lee they knew the suspension and chassis would twist and buckle taking the kinetic energy out of the landing impact. They where always OK after ever jump because you would see them drive away from were the General Lee hit the ground.

[@afrodesiac8064]

I accidentally rode my bicycle into our closed garage door as a child. I was probably going about 6 to 10 MPH on impact. It was discovered my tires had no tread, which was probably why I had trouble stopping. My face hit the garage door and I have never had a lip so swollen.

[@joseimpact]

haha funny but mest up story i hope your okay haha

[@afrodesiac8064]

@@joseimpact thanks. Yeah, just a very swollen upper lip. I got some looks at school the next day. No other injuries that I can remember. Hey, have I ever told you about the time I rode my bicycle into a garage door?

[@LD10000]

I had a freshman-physics professor who explained this in kinematics and inertial forces. Thank you guys, I probably would have got more out of physics class if you were teaching.

[@kencochrane2885]

Perhaps you would have done better if your physics professor wasn't a freshman, had he finished his masters or PHD he would of had a better chance teaching. 🙂JJ

[@LD10000]

@@kencochrane2885 Lol

[@davidmurphy563]

Yaay, I get to correct NdGT: Hussain Bolt reached 27.8 mph / 44.7 kph. The man can move.

[@ps-qw7gp]

My maan 👍🏾

[@prettycountrygirl2]

Very humorous and informative video. When I first noticed the title, I thought that this video would be boring - I'm glad that I watched it throughout.

[@JoshSmith-rk8cr]

If an airbag deploys at 100-220 mph then say your airbag is deploying at a speed of 100 mph. Now let’s also say you are driving your car 150mph and you crash into a building 150mph-0mph instantly. Will your airbag be able to hit you before your face hits the steering wheel?

[@EaastonCams]

Hmm brb I’ll experiment.

[@rememberingthefuture9500]

Airbags are designed for public roads governed by speed limits that are less than 100 mph. While there are some roads in some parts of the world that have no speed restriction, they are in locations where the chances of colliding with a stationary object are almost zero. I guess airbag designers saw no merit in designing an airbag to protect some speeding drongo from their own stupidity.

[@ChicagoBornPilsenBred21]

Always interesting & fun to watch these 2💯

[@Owyourhurtingme]

My god I love this man!! He is todays Carl Sagan but slightly cooler.

[@ManaBDew]

Pluto all this time & I never expected to get in a wreck involving Dr. Neil deGrasse Tyson I stopped being a planet. Like instantly 👋🤩👍

[@dorianrichardson7669]

Please do a video on truck driver accident’s

[@camelfilters3224]

We need the safety system they used in "Demolition Man" where it was some type of hardening foam to protect the driver.

[@ebredenberg]

Going fast never killed anyone. Sudden and unexpectedly stopping is what takes you out.

[@greatlakesuperiordeepviewsvide]

I survived 2 very high-speed crashes in Dodge Darts that required the jaws of life to extract me from the wreckage 🤕 But the unibody took the energy and bought some time to slow down before the engine was next to me and I survived with minor cuts and bruises.

[@whitsrcleftovers2707]

Physics my Jr year of high school we did the calculations to find out how fast you could go from moving to a dead stop, based on your weight, and hold yourself from hitting the steering wheel. The average was in the single digits.

[@dorianrichardson7669]

That’s how use truck driver live. I’m a flatbed driver and keeping distances are vital. The saying is we truck drivers are rolling rockets. 65mph is catastrophic weighing up to a max of 80,000lbs

[@thehermitman822]

Knew a guy that believed everyone should have to drive a motorcycle and a semi for 6 months to understand the dangers on the road. It's not exactly an awful idea but I imagine all the wrecks caused by those new drivers as well.

[@andrewlindenfeld6222]

Yup, fellow truck driver here. It’s terrifying the amount of kinetic energy in your rig when you’re going 20mph, let alone highway speed.

[@macysondheim]

@@thehermitman822 Actually it is exactly a terrible idea. Hopefully this “guy” never gets put in a position to make any kind of important decisions. But we both know this “guy,” is you….

[@sushicraves]

A truck has a lot of mass behind it when it hits A car that 200 t of mass is transmitted to the passenger car. That's why when you look at a passenger car that's been ruined by our truck. The back seat ends up being in the front seat

[@richard_d_bird]

people sometimes learn a lot about kinetics, really fast

[@Goldengirl48]

I was in car accident that the car hit a brick wall. I was not wearing a seat belt and was sitting in the center of the front seat. I was thrown up into the windshield. The only thing that saved me from going through windshield was the rear view mirror. I ended up in the hospital with a fractured vertebrae in my neck and the side of face was badly torn up by my glasses.

[@128Benja]

For martial artists also learn this. I studied Aikido, and they show you how to balance the weight of the fall with either standing or sort of hitting the ground first. The hit in the ground mitigates most of the fall kinetic force in the rest of the body.

[@stevebrindle1724]

I learned the same thing whilst studying the martial art of northern England-Ecky Thump!

[@rjsmith6698]

Reminds me of what someone told me many years ago. He said there are 2 kinds of car accidents, the ones where you yell, (and he didn’t use this word) “CRAP!” and the ones where you yell, “CRAAAAAAP!!”😄

[@R0bobb1e]

another question to do with arresting kinetic energy is. If a skydiver's chute doesn't open and they hit water at terminal velocity, they will, generally, die. Would it make any difference at all if someone saw and sprayed the area with detergent, thus breaking the surface tension of the water?

[@zuzu2700]

No it wouldn't. Surface tension is very weak, it just allows insects to walk on water. What happens when you fall into water is compression. The water can't move out of the way in time and therefore appears hard. Hence, if you extend the time it takes as mentioned in the video, you would just fall into the water normally. Same thing really. Side note: compression is also what causes objects that travel at very high speeds through the air, like meteorites or de-orbiting satellites, to heat up and glow.

[@annabarseghyan9791]

“Did you go to a budget circus?” 🤣

[@Jack_McKalling]

You don't need a parashute to go skydiving. You need a parashute to go skydiving twice.

[@super60sand70s]

Yes, Chuck, the train is the way to go. And after an accident like I had I was no longer able to drive and I am riding a train to/from work. So, the train should have been my mode of travel all along.

[@thomasjenkinson728]

Interesting fact in the UK we've rebranded accidents as collisions! Accidents imply nobodies fault. Except there is always the human factor so somebody is always to blame in a collision! Accidents do not happen!

[@chrisostling805]

I had an experience that most people cannot explain 3 years ago. The marine propane heater on my sailboat exploded in my face, it blew the decks and pilot house over 40' into the air and they landed back in place upside down on what was left of the boat. The sides and transom split apart, and it sank in minutes. I was literally at ground zero, yet the blast did not even move me and did not even blow my hat off, the fireball was another story though I healed with no visible scars. I was in the main cabin in the lowest part of the boat, if I had been anywhere else inside or next to the boat it would have surely killed me. The US Coast Guard cannot figure out how I survived, I think that it was because I was at ground zero, that the pressure wave was not yet strong enough to affect me, though it was very surreal having the entire boat blow away from me in complete silence, I was obviously in a vacuum during the explosion hence the lack of sound. Am I close to an explanation?

[@josepht5331]

As a firefighter this makes perfect sense. I’ve seen so many car accidents where the outside of the car is completely destroyed but the passenger compartment is still intact and the person is perfectly fine or at the very most has a couple of scratches and bruises. It’s called compartment intrusion and it’s probably the most important information u can have to determine how injured a person will be.

[@Zab0Zab0]

True, a soccer player would scream in agony if you touch him lightly, but he would stoically stand still if you hit him with the ball kicked at full speed since that's not foul. 😉

[@jrooks]

I have a question about sound. If a group of people are together at an event and an emergency alert sounds on everybody's phones at a set volume per phone, does the number of phones make it louder?

[@Romamb]

Try it out for yourself.

[@chillskeleton6529]

Is ten people screaming louder than 1?

[@michaelccopelandsr7120]

A person yelling compared to a stadium full of people yelling. Survey says....

[@davidmurphy563]

It depends... Sound is a wave, air particles pushing against other air particles. So, when waves collide they add. But sometimes waves are negative and sometimes they're positive. So when you get "constructive interference", they combine and the sound gets louder. When you get "destructive interference" then can cancel each other out and you can end up with silence if you get it just right. I bought my dad some noise cancelling headphones this week, and I believe they use destructive interference - they sample the external noise and literally produce noise in the ear order to make it quieter. You get the same effect with light as well; the famous double slit experiment for example. Not to mention waves on water, same thing.

[@Sammasambuddha]

So, it is louder, but only if the phones are doing the 'wave'?

[@janewayofchaos3255]

This makes me wonder how we will deal with stopping once we are able to reach near light speeds.

[@damianmlamb]

It's more of a teleport than actually traveling your folding space to bring the other location to you.

[@PeterKnagge]

First half of journey accelerating to light speed, second half of journey decelerating to stop.

[@janewayofchaos3255]

@@damianmlamb depends on which method we use. The folding of space could potentially accelerate an object to faster than light, but would require some form of warp bubble to hold the object in.

[@YM-zz5qq]

I’m not sure why anyone would want or need to travel at light speed. 🤔

[@ivanlupi]

We need more like these! And by that I mean two awesome humans sharing knowledge that helps people thinking to their advantage while smiling all the way through. Thank you 🙏🏻

[@diesel46809]

It's not the fall that kills you, it's the sudden stop.

[@Kacpa2]

This is so true because most deadly accidents are quite understated and seemingly nondramatic. Ayrton Senna died in an accident that looked quite uneventful compared more theatrical collisions.

[@azedinelyakoubi7887]

Always interesting & fun to watch😃

[@super60sand70s]

Loved this video. I was rear ended in a car accident 35 years ago where the driver hitting me was going 55 mph. I was stopped at a light and my car hit the truck in front of me with such force that my car turned upside down, then righted itself and 3 more times before my car stopped. My seatbelt had to be cut off with scissors. I have had a ton of medical problems since then but I have always been curious why my car tipped over 3 times before stopping.

[@douglasiles2024]

Cutting the seatbelt with scissors just makes it easier to get you out. With the damage to your vehicle, the seat belt isn't going to be used again anyway.

[@super60sand70s]

@@douglasiles2024 you are hilarious! What I should have said was that the force of the impact made the seat belt tighten so much that it would not come off. A police officer had to find a pair of scissors to cut it and free me.

[@douglasiles2024]

I've worked a pot of car accidents, and cut many seatbelts off of patients. It just makes things easier, regardless of how tight the seatbelt is against the patient.

[@jasoncallahan344]

This reminds me of a video where a guy jumped out of a helicopter at 2,500ft with just a wing suit and landed on a bunch of cardboard boxes and walked away.

[@davidbranagan9429]

17 year-old Juliane Koepcke was sucked out of an airplane after it was struck by a bolt of lightning. She fell 2 miles to the ground, strapped to her seat and survived after she endured 10 days in the Amazon Jungle. Lansa 508 crash 1971. Amazing.

[@MarioDallaRiva]

Check out this year’s British F1 GP race incident where the Chinese pilot in the Alfa walked away from insane G-forces sustained in a barrel roll at high speed into the catch fence.

[@michaelccopelandsr7120]

Neil and Chuck for 2024

[@JohnnyAllen_]

Wow this makes me appreciate my life more after rolling my car a few years ago and narrowly missing some power poles which wouldn't have let my car slow down over a few seconds

[@christophelombardi7810]

Speaking of collisions and resulting damage, Neil & Chuck, you should do a sport's edition on collision in both American Football and in Rugby. Two sports with plenty of contact, even though they're not done exactly in the same way, one of them with plenty of protections and the other one with absolutely nothing. It doesn't mean that football players are better off, mind you, because the head collisions you see in Football only happen rarely and accidentally in Rugby. Still, both sports are rich in 'contact' and it'd be interesting to review them under the miscroscope of Physics.

[@jb-zc9dm]

There's a flight attendant that got sucked out at crusing altitude. Around 30 thousand feet and survived. Maybe it's a physics thing but it's still a maricle in my opinion if not just super lucky....

[@philipberthiaume2314]

Withstanding that this is startalk, a fantastic analogy was missed. Neil might have chatted about the differences between Soviet and American capsule landings. Soviet capsules would land on hard ground and would require retro rockets to soften the blow, while Americans landed in the ocean. Perhaps this analogy could be dissected further in another explainer video...

[@feedingravens]

I'd say the russians had no choice. While the US has plenty of coastline in front of which you can do a splashdown, Russia simply has nothing in moderate to warm regions. But enormous plains.

[@Dead_Z]

When I was in the police explorers there was this gadget that you sat in a car seat with a seat belt on that slid down a incline that would suddenly stop to show that seat belts are important and it is very hard to hold. yourself without a belt.

[@waywardgoddess7219]

I was turning and got tboned at roughly 25mph. The impact at that low speed still jolted tf outta me, spun my car 360, totaled it and the airbags went off. I always wear my seatbelt but thankfully the impact was on the rear passenger side because as a short person I'm doomed to be too close to the wheel/airbag. I also didn't hesitant for a minute being glad my car was totaled and not me.

[@jpdemer5]

I ran head-on into a wrong-way driver on a freeway ramp - both cars probably going about 40 at the time. Belts and bags worked as advertised - somewhat surprising that going from 40 to zero in half a second is not even uncomfortable, when the forces are spread out over your upper body and not concentrated on your face.

[@frankbarnwell____]

Don't put your tool belt in the passenger seat. Got hit with a claw hammer in the neck. Damn near bled out in a frontal collision that otherwise I'd have walk from. Other heavy stuff in the car can do the same.

[@robertcampomizzi7988]

"Any crash you walk away from is a good one" - Launchpad McQuack

[@jeffo4817]

Absolutely no one thought dale earnhardt was dead by watching that crash.

[@SMHman666]

Jeff O Yeah, compared to other crashes his one looked pretty soft.

[@fc-qr1cy]

14:32 as a life long fan of soccer. That was so wrong but true. Neil and Chuck got jokes. LOL

[@PeterKnagge]

I'm not American or English so it doesn't hurt my pride, but baseballers usually wear protection similar to cricket players. Smaller harder ball with more kinetic energy in a concentrated area, yes it will hurt in an unprotected area. However soccer has no protection other than shin guards and has a larger inflatable ball, more surface area and full force league headshot into the face will also hurt a lot, I don't care who you are! Obviously the overacting is appealing to ref for sneaky penalty shots and part of the game strategy.

[@josemiguelmontes491]

Another physics concept at play here is pressure whenever the body "hits" something inside the car. The damage the body experiences depends on the force, but also on the size of the area that receives the impact. That's why seatbelts are wide, and why a punch causes more damage than a slap.

[@TheEmilpedersen]

Thanks for this late night upload, (Europe

[@l2etranger]

That plaque should revive travelers with a smile 🛬💺😅.

[@snajperSLO]

What makes a collision lethal? The ending…

[@microchip5673]

Just blame gravity

[@dearcath]

Things that only make sense in a car crash- Roll once -> dead Roll once more -> Alive

[@Naught359]

Stopping fast, is the answer.

[@Joonzi]

There have been many new images coming from JWST since the only explainer that was made about it. We need a new one please. Thank you.

[@jakeloranger1419]

I read somewhere that in the early days of Formula One racing the cars were made rock solid. The problem was that in an accident, while the car sustained minimal damage, the driver invariably died. So then cars were designed to dissipate the kinetic energy to spare the drivers. This has led to more spectacular car crashes, with car parts flying all around (the open wheel design of F1 cars often propels the cars skyward as the wheels climb over another car). But the driver quite often walks away. As Neil said, as long as the driver's space doesn't get crushed, the driver will be okay. I do want to thank Neil for explaining what happens inside the human body when it takes on the full kinetic force of an impact. I wasn't clear on how those early F1 drivers died, in terms of the physics involved. Now I know. Which I guess is the whole point of this show. Well done.

[@kenna5031]

It's also the same effect with sudden acceleration. You could also die. In both cases, the basic question is, how many Gs are you exposed to? Oh by the way, it applies to both change of speed and change of direction, better referred to as change in velocity.

[@bobcornwell403]

Interesting brining baseball into this. One particular hazard is aluminum bats. They don't break but more efficiently transmit the energy to the ball. This is normally what is desired--except when the ball hits an infielder in the head--sometimes with fatal results.

[@Keze13]

"What makes a collision lethal?" Same thing that makes falling from heights lethal... the sudden impact/g-force. Everything is fun and games until then.

[@chrisostling805]

Back in 72' our neighbors got T-Boned by a fully loaded log truck doing 60 MPH, luckily, they were in their 72' Volvo 164E, the worst injury was a bruise from a seat belt. I saw the car at the wrecking yard, there was not a single straight piece of sheet metal, but all the windows survived, and the only broken glass was from the rearview mirror on the side it got hit. Also, Volvo was the first to develop and equip their cars with shoulder harnesses in the 3-point configuration, they refused to patent the idea, so it was free for everyone else to use because it was more important to save lives than make a profit.

[@d34n_]

To apply this concept to a different scenario, if you were running towards a wall and you couldn’t fully slow down before you hit the wall, what’s your reaction? You put your hands out to slow yourself down even more before your body hits.

[@randyb359]

I think you are missing an important factor. While physics is why you survive, the reason those physics worked the way they did was because of the engineers that designed it.

[@ChandraNYC]

Incorrect: Engineers design the way that they do, because of their understanding of Physics.

[@thearthurmigliazza]

I love startalk and always learn so much from these guys

[@mfst100]

Neil could've mention two more things to make it more interesting for people out there: 1) that sometimes firm cushion in helmet is better than softer one. 2) that head to head colision of two identical cars is slightly more safe than hitting concrete wall head on. Both are sometimes couterintuitive for people.

[@judassantacruz4071]

Chuck is BACK!!! :)

[@joseimpact]

i got in a car crash well some guy did a hit and run to me. and my car spun out but thankfully i was wearing my seatbelt. please wear them

[@kenchan4774]

The Earnhardt crash shocked me. I remember watching it as a kid thinking it was just a typical Nascar crash until they showed the car cam colliding with the wall. Also, the Dan Wheldon one looked horrific in comparison, but both had deadly results.

[@iauggyi]

Really enjoy this show. I have maybe a good idea for star talk sports addition. I skateboard and I realize that skateboarder are scientist in a way. The skateboard itself is filled with physics like where you put your feet to do tricks and the fact that you need to hit the boards tail to the ground to get the Board up in the air. I don’t know just an idea either way very glad I discovered your show.

[@carguy-xv2cl]

Sports is boring.