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• Diandra Leslie-Pelecky: I thought that was really creative

• and totally possible.

• My name is Diandra Leslie-Pelecky.

• I have a PhD in physics, and I started off my life

• as a condensed-matter physicist working in nanomedicine.

• Along the way, I ended up writing a book called

• "The Physics of NASCAR."

• So today I'm gonna use that knowledge

• to talk to you about some clips

• from "Fast and Furious."

• This is one that is a little difficult to analyze,

• because you're not quite sure how long they're falling.

• It could be anywhere from 11 seconds to maybe 15 seconds.

• That's a really long time to fall.

• I calculated out

• what Dom's terminal velocity would be,

• and that's biggest velocity you can fall

• given that drag gets bigger as the speed goes up.

• And he almost approaches it.

• After 11 seconds,

• Dom would be going 124 miles per hour

• when he hit the water.

• He would have fallen about 1,775 feet

• at that point.

• Now, 124 miles per hour into water,

• maybe that's survivable.

• Laso Schaller holds the record for the highest jump.

• That was from 193 feet.

• He hit the water at 76 miles an hour.

• He broke his right clavicle and dislocated his pelvis.

• The Golden Gate Bridge is about 245 feet.

• People hit the water at 86 miles an hour.

• Only 5% of the people who jump survive.

• So the probability of them surviving is pretty small.

• They built a launcher and took this beautiful

• 1966 Corvette and actually launched it

• off the side of the cliff,

• and then they had stuntmen

• who did it separately from the car

• because being hit by a car midair

• would be worse than actually hitting the water.

• And so they had the stuntmen do it,

• but the stuntmen were on cables.

• Then they came back, did it on a green screen

• with the actual actors, who were, you know,

• maybe eight feet above the ground.

• But this one I think I would have to give a score

• of two, because there's absolutely no way

• they could've survived a jump that long.

• So, this a 1969 Camaro.

• It's got a mass of about 3,500 pounds.

• So, they're hitting 90, so you know

• the boat's going at least 90 miles an hour.

• One of the things that you notice is that

• when the car and the boat are both speeding along,

• they're parallel to each other.

• Now, how they all of a sudden get behind the boat,

• I'm not actually sure how that happens.

• But let's assume they can do that.

• When they take off, they're going at approximately

• 45-degree angle off this ramp,

• and they're going 120 miles an hour.

• So not all of the speed

• is taking them in a horizontal direction.

• So I've taken cosine of 45; they're only now going

• about 78 miles per hour toward the boat.

• Now, that's a problem,

• because the boat and the car looked like

• they were going the same speed.

• And the problem is, if the boat's going 100 miles per hour,

• it'll be 1,200 feet from the shore.

• The problem is, the car can only go 945 feet

• in the time it's in the air.

• There's actually no way

• that the car could make it onto the boat.

• Let's pretend the boat is only going 78 miles an hour,

• because if they are, it's totally possible.

• It is going fast enough, and it makes up

• all the distance between it and the boat.

• So if you include drag,

• they're gonna lose some of their speed

• due to air resistance.

• They're still gonna hit that boat

• at around 105 miles per hour.

• The kinetic energy of the car

• and the guys in the car, at that point,

• is equal to about a fifth of a pound of TNT.

• Some of that goes into wrecking the boat

• and wrecking the car, but not all of it.

• Which means some of it is gonna go into the guys,

• and they're gonna have a whole lot worse

• than a broken arm.

• I think I'd give it probably a seven out of 10,

• because it's possible it could happen.

• They had to modify this tank

• so it could go 60 miles an hour,

• 'cause they normally only go 30 miles an hour.

• Dom, we'll assume his car was going 60 miles an hour,

• so when he left it, he was going 60 miles an hour.

• So you can look at conservation of momentum

• and figure out that by the time they hit and continued on,

• they were probably going around 40 miles an hour.

• So a little bit of change in speed,

• but the problem is when he hit the car

• going 40 miles an hour, and she is about 120 pounds,

• he's about 225, so you're talking about 340 or so pounds.

• You're gonna be hitting it with an acceleration

• of almost 100 g.

• They have no protective gear.

• So, you know, race-car drivers

• routinely survive hits of 100 g.

• They've got a big car around them.

• And maybe it's possible that Dom could launch himself

• at just the right angle to intercept Letty.

• And then maybe it's possible that

• that path took you onto the second bridge

• instead of over the first one,

• and maybe it's possible that there happened to be a car

• at the point where they were landing,

• and maybe it's possible

• they survived hitting the car together.

• Each one of those things might have happened,

• but all four of them together

• is just too much of a coincidence.

• Once you're in the air, you cannot steer.

• So if you misjudge in any way,

• you're gonna miss her.

• Now, if you watch baseball players,

• they develop this very intuitive ability

• to know the arc of a ball.

• And after all, it's just a parabolic motion.

• Maybe just Dom understands physics so well

• that he knew exactly where to launch himself.

• And if you talk to a race-car driver,

• they would be able to understand centripetal acceleration

• and explain it to you. Again, no equations,

• but they get this intuitive understanding for it.

• So, it's just possible, maybe Dom has

• rescued enough people who are flying through the air

• that he understands how to do it.

• Hollywood has its own physics.

• One of the rules is they have time dilation,

• which is that when something really exciting is happening,

• it can take as long as you want it to take.

• Slowing down, let's say 120 miles an hour,

• and I pick that number only because

• that'll tell you, at 120 miles an hour,

• the car is going two miles every minute.

• So for every minute of that clip,

• you're traveling two miles.

• The longest airport runway in the word is 3.4 miles,

• which means if they were on that runway,

• this still could take 1.7 minutes.

• And it doesn't.

• It takes a lot, it takes, like, 11 or 12 minutes,

• which would result in just this unfathomably long runway.

• OK, so Dom is driving a 2012 Dodge Charger,

• and let's pretend this is a super-reinforced version

• of a Dodge Charger.

• He doesn't have a lot of time to get up speed.

• Because he's only got the inside of a plane,

• and as you saw from the fight that was going on,

• there's not a lot of room.

• I think I have to give a one.

• Just because here,

• they stretched my ability to ignore reality

• just a little further than I'm capable of doing.

• Try to figure out how much that vault weighs,

• according to the storyline.

• So, we're gonna assume it's a 5-ton vault.