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The Science of Hollywood: Hacking All the Internets With Only 10% of Your Brain
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It's the understandings he has trouble with
Only in the movie. In the book:
What about Das Boot?
Effectively, they're cutting gravity drag to zero by flying down into the planet. They'll incur gravity drag again on the way out, but that trip is going to be much shorter. If, in reality, we could make the Earth transparent to spaceships we'd launch downwards on every single space launch.
Put another way, they're unable to achieve escape velocity because their thrust/weight ratio is less than 1. The ship can't increase its specific orbital energy by accelerating upward. But their spaceship is (nearly) stationary--so they can increase their specific orbital energy by applying an engine burn downwards or side-to-side just as well. Going side-to-side or downwards is ordinarily impossible because the ship would collide with the planet, but in this case ~space magic~ happened and the planet is traversible.
It makes perfect sense, given the absurd premise (and that we're apparently neglecting air resistance), to accelerate downward through the planet to escape it. It might help to imagine the spaceship doing this repeatedly (i.e. yo-yo-ing back and forth through the planet) applying thrust on the way down. Each oscillation brings it higher and higher, and at no point does it need any particular thrust to weight ratio to eventually reach escape velocity.
And Saved by the Bell Screech invented a sentient robot named Kevin and no one made a big deal about it!
Great point.
From the start (40,000m, 0m, 0m), they'll be accelerating towards (0m,0m,0m) at ~9.8m/s^2* + (engine/mass). Then, they'll hit "turnover", and begin decelerating at (engine/mass) - ~9.8m/s2. So, assuming they start at rest (because why not?), their time to go from (40,000m,0m,0m) will be less than their time to go to (-40,000m,0m,0m), even if you also assume that the change in fuel mass is 0 (because sci-fi), and therefore skip imortant parts of the Oberth effect.
So, when they reach 40km on the opposite side of the planet, they won't be at rest.
Basically, I forgot the engine.
* This actually should start decreasing as you move towards the center, and hits 0 at the center because you're being pulled equally in all directions at that point. But, it does it symmetrically on each side of the centerpoint (by distance from the centerpoint).
Steam: Elvenshae // PSN: Elvenshae // WotC: Elvenshae
Wilds of Aladrion: [https://forums.penny-arcade.com/discussion/comment/43159014/#Comment_43159014]Ellandryn[/url]
Also, all cars have infinite gears.
I'm not a doctor or anything, but I figure if you ram the butt of your rifle into someone's head so hard that they lose consciousness, you've probably killed them.
Nope, it's not. My sister is the doctor in the family, and I've got to hear some pretty 0_o stories about the damage you do performing CPR.
Back on guns, you don't see it often, but silencers on revolvers. Aside from a couple special exceptions, suppressors don't work on revolvers, because there are multiple unsealed gaps aside from the barrel for the booming and the gas to vent through. I remember watching 'The Sting' for the first time, and when I saw a shot of a pair of ominous hands screwing a suppressor onto a revolver, I thought for sure it was going to pop up as a part of some scam or con, but nope, next scene you've got the revolver going fwip fwip fwip!
The thing is, mistakes in media are typically forgivable, especially when it fits into enhancing the sense of verisimilitude of what's happening. Maybe in hindsight, you start to think about something and realize it wasn't quite right, but at the time it was okay. The problem is when right there in the middle of a scene, something happens that makes you sit up and go, 'that's not right!' or the hindsight revelation actually ruins things.
And yeah, I've heard about stuff like broken ribs and whatnot from CPR, but that's what happens when you're trying to externally and repeatedly apply enough force to deform the structure of the very ribcage that's supposed to keep things from screwing with your heart and lungs. But they can't really spend 20-30 minutes showing actual CPR in an hour-long show, I suppose.
And this is Hollywood. What else can you expect from an industry where people major in stuff like cinematography and writing, but have little to no experience with hard science? Hell, they can't even have a science lab around without trying to sexy it up with fancy lighting and people doing labwork in well-coordinated clothes instead of, I don't know, lab coats and goggles? Such as those required by federal safety regulations?
It's not about "losing force into the object" it's about the surface area of the object you're hitting with. Generally there are two effects at play when you hit an object into an other object
1) the absorption of energy of your fist.
2) the surface area of the area striking the target.
Point the first occurs regardless of the object (so long as it wasn't strapped to your arm for the entire punch) and so is the same for the book or shield or whatever. The second is worse for the book because the surface area is larger and so the impact area is less damaging.
Handheld blunt weapons work in at least one of three ways
1) leverage: allows faster and more energy at the connection point
2) surface area: smaller to make more impactful wounds
3) mass: heavier means more damage.
Brass knuckles are an easy example. They are heavy have a small surface area and have a backstop that connects the wrist to the knuckle. The backstop prevents the fist from absorbing much energy (whereas the arm is much more rigid), the lowered surface area increases the damage, and the extra mass allows more energy transfer.
Hitting someone with a book would work but punching a book would be like punching armor. Not very effective armor but armor none the less. The book transfers the energy to a wide area before imparting it in the body. Additionally the book may hurt the attacker more because it's harder than flesh.
and forget breaking ribs, that's the relatively non-squicky part. The part where you have to keep the airway clear while the person vomits up various material is the squicky part, even assuming you have adequate barriers to work with
that's why we call it the struggle, you're supposed to sweat
that's why we call it the struggle, you're supposed to sweat
that's why we call it the struggle, you're supposed to sweat
This is what advisors are for. I can get giving things more visual flair than reality, simplifying to keep things easy for the audience, or shortening time to keep narrative pacing, but it's not much to ask that they throw some chump change at a person in a relevant field to sign a few NDAs, come on set (or read over script material/concept artwork, talk to the writers/set designers/costume designers, whatever), and give a basic idea of how things are done in reality.
Old PA forum lookalike style for the new forums | My ko-fi donation thing.
It's a tie between the idea that ALL guns have a safety mechanism and the reinforcement that the "palming a tea cup" grip is the proper way to hold and shoot a pistol.
that's why we call it the struggle, you're supposed to sweat
Our intrepid heroes jump into their Space Buggy and lift off from the planet. However, the engines just can't thrust enough to achieve "Escape Velocity" - they'll have to lighten their load. After throwing out all non-essential items, the computer informs them that they still have too much weight. The amount of additional weight they need to lose is equal to... one human being. The heroes eye each other nervously...
The problem is gravity doesn't work like that. The formula for the force of gravity is G(m1*m2)/d^2 (sometimes denoted as r^2). Once you've taken off gravity doesn't act like a rubber band, pulling you back unless you suddenly break free - it just becomes exponentially weaker and weaker as you move farther and farther away.
What "Escape Velocity" means is the initial velocity required for an unpowered object to overcome the effects of gravity. As the unpowered object travels away from the gravity source, it slows down - but the rate of change in velocity is different to the rate of change in the force of gravity. If the initial velocity is greater than escape velocity, the rate of change in the force of gravity is sufficient that it becomes negligible before the object comes to a stop (and before it starts falling back down).
However, as soon as you add power to the situation, "Escape Velocity" becomes meaningless. Assuming you have sufficient power to get even 1 inch off the surface, as long as you continue to have power you can continue to move at 1-inch increments forever - and since gravity becomes weaker as you move away, eventually you'll be able to move at 2-inch increments, then 3-inch increments, and so on.
So unless the planet is somehow magically adding mass to itself or the Space Buggy runs out of fuel, there's no reason why they need to do anything to escape the gravity well.
Don't most of the 1-punch deaths happen because the victims hit their head as they fall?
Not that this disarms any of the other criticisms.
No, it's very much about the loss of applied force due to the elasticity of the medium you are using (either book or shield or whatever). The object in question won't just perfectly transfer the force. It will absorb it as well. That's why punching a book vs a pillow will transfer differing amounts of force to the person on the other side of the object.
Handheld blunt weapons also work due to being rigid and thus better at transferring force from your arm to the target.
2012 had its amazing THE NEUTRINOS HAVE MUTATED moment.
Independence Day hacked an alien spaceship with a laptop.
Choose Your Own Chat 1 Choose Your Own Chat 2 Choose Your Own Chat 3
I actually forgot this plot point when I watched it for the second time - it was like my brain actively rebelled against having that idea inside it./
I think we need to literally do the math.
So so so so much wrong with that scene. It was a Fast & Furious movie so I had formally detached my brain and all but that got through. So much pain.
Yep. CPR is not really a life saving procedure, it's a life sustaining procedure that you do until people with actual medical equipment show up and take over. Which is not something they stress much because it can be pretty demoralizing.
When I trained as an EMT we were taught the Precordial Thump even though I think it was out of the standard even then. It was also part of the "If you can get them to help, DON'T DO THIS!" since even done correctly it causes a bunch of damage. Some show from the 70's loved this maneuver but it seems Hollywood decided maybe they should stop encouraging people to bash heart attack victims in the chest instead of doing CPR.
Of that's another one, when the EMT's say "Oh no, he's having a heart attack!" in front of the patient? Yea, on the list of things to NOT do that's pretty high up there. It seems most people hear the words "Heart Attack" they get a little stressed out which isn't good for you in the middle of a myocardial infarction.
The thing is, the item you're hitting is a hard material (a book or a metal shield). A punch is more along the lines of hitting someone with a mace than with an axe. What I mean is, the purpose is to delivery a lot of force over a larger area, rather than over a narrow cutting edge.
Your fist is intrinsically a soft, pliable material. When you punch someone, a significant amount of your energy is used up in deforming this material. The same is true of a face. By introducing a hard medium between the two, that is not pliable, you transfer more of your punching energy because you greatly mitigate the fact that your fist and their face are pliable. The loss in pressure is trivial (all the force is transferred via conservations of momentum and energy).
To see this in action, look up the Mythbusters episode where they were trying to recreate what happens when a bird hits an airplane window in flight. The thawed birds would bounce right off. A frozen chicken, however, blew straight through like a bullet.
There's a lot of things wrong with that experiment. Mostly that in real life a regular bird will go right through the cockpit window and the cockpit door. Hell one of the bird strikes I worked had taken out 4 yards of composite panels and the solid steel inch thick structural beams beneath.
When the alien's scout ship crashed in Roswell it was brought to Area 51 and studied. Most of the major technological advancements over the ensuing decades were brought about from reverse engineering various components on the ship over time.
Basically it worked because the PPC CPU in a Powerbook 5300 was derived from alien tech.
They sorta explain it in a scene that ended up getting deleted from the film, and although it's pretty flimsy story wise at least the writers tried, which is more than most do with tech stuff.
On the subject of hearing damage from firearms in movies, there is a great scene in The Sopranos where a guy sitting in the passenger seat of a car with the windows up shoots the driver, then yells AW FUCK and grabs his left ear in pain while continuing to shoot.
If they can provide enough force to get 1 foot off the ground, they can provide enough force to get all the way out. Because, presumably, their engines keep going with the same force. Usually, a normal rocket can't just keep firing its engines forever, but this one can.
However, in a world of limited fuel, the trick would have worked. If the problem had been "we don't have enough fuel to keep this up long enough to get out" then flying through the planet while accelerating would have made a difference.
I mean it is still incredibly, incredibly dumb for any number of astronomy and physics reasons (Whatever blew up the planet seems to me incredibly likely to leave an incredibly hot plasma around normally, flying through it would melt any spaceship not made out of unobtanium).
In the opposite of this, in Armaggedon there is a tense jump when they're on the asteroid getting from one section to another. Only with the given size of the asteroid the escape velocity is in the single meters per second, and they should've easily hit escape velocity and just drifted into space.
Hall of Famers in the Astronomy Section are of course, Asteroid Belts/Fields.
Our own asteroid belt yields a 1km big rock every few million miles, and even if you limit it to 1meter big rocks you still end up well in the 100,000s of mile estimate range (Such small rocks are hard to see from here)
Flying through one isn't much of a challenge for any spaceship.
The amount of pushback the average person takes from a gunshot is of course also off by several degrees of magnitude.
I will also want to have a lifetime achievement award of bad movie science for anything and everything mentioning the word quantum.
Quantum does not in any way give you the right to claim "Anything can happen" or "We don't really know how this works, it's magic"
But it gave us this!
Let's play Mario Kart or something...