Amusing science misconceptions

[Iori_Yagami]

I somehow feel that this belongs to general, but if it is really adequate for science part, so be it - move it.
I have gathered some of the most funny scientific misconceptions. They all have one thing in common - they define something without integrating it with already existing things, thus failing to explain phenomena, but rather complicating it unneedely.

1. Water filter does not let any particles to get through, only water can flow freely. (water itself is also composed of particles, so tiny particles dissolved can get through perfectly);
2. Electricity causes electrons to move (charge movement itself is electric flow or current, in static electricity there is no movement at all - just charge separation);
3. Epidermis is a thing which covers and protects skin. (it is itself part of skin - top layer);
4. Heat causes molecules to move faster (heat itself is the movement of molecules).

I may be not very accurate, but you hopefully get the general idea. Feel free to contribute.

[Solt]

You will catch a cold if you get wet in the rain.
Summer happens because the earth is closer to the sun in the summer.
Raindrops are shaped like teardrops.
You can kill someone by dropping a penny off the empire state building.
Hydrogen fuel cells are an energy source.


And fyi, electricity DOES cause electrons to move. Direct Current, anyway. And heat is the transfer of energy, not the energy of molecules, so I guess it would cause things to move faster.

[Gelsamel]

<insert psuedo-science/supernatural-thing here> is actual science, and actually works.

[Hawknc]

Airflow over a wing somehow "must" meet up at the trailing edge, so the faster flow over the longer top side causes lower pressure and thus lift. (Ugh. That's a common misconception even among first-year AE students.)

[hyperion]

Airflow over a wing somehow "must" meet up at the trailing edge, so the faster flow over the longer top side causes lower pressure and thus lift. (Ugh. That's a common misconception even among first-year AE students.(

I was just about to mention that. Who's the idiot that came up with the idea that air has a brain?

Also: that polar bears' fur is clear, not white. "It just scatters all frequencies of light". That's the fucking definition of white.

[JonMW]

The polar bear fur thing is a grey area, I think. If you looked at a single hair really, REALLY closely, the idea is that you'd be able to see through it - but the image would be distorted, as though your were looking at a tiny rod of glass.
When you say that something is "white", many people will assume that it is opaque, which is the misconseption that they are trying to dispel.

[Iori_Yagami]

Well, thanks, but did you carefully read my post?
Did you notice the specifics of those misconceptions?
The general pattern is:
A [relation] B, therefore [something]
In reality, A [isA] B, or A [hasA] B.

Okay, electricity is very, very confusing and poorly taught thing. Try to google for many intresting discoveries. In reality, term 'electricity' is not physics, just as termn 'many' is not mathematics. Current is the flow of charge, but it itself does not flow. If you see a river with a current, it is water that flows, not current. Current cannot flow.
If you want to be confused even more, try to guess the speed of electrons in typical wire. What? Nearly to c? Oh no, you are wrong - it is electomagnetic field which has such speed; electrons themselves move at velocity of several centimeters per second.
It might be simpler, if we imagine a pipe full of tiny balls. Push the ball on left pipe opening into pipe and continue pushing. The balls will fall out of the other end, and will move somewhat slow, but time between your push on one side and ball falling out of the other is nearly instant, impulse is carried very fast.

[b.i.o]

Schizophrenia and Multiple Personality Disorder are the same thing.

It was the first misconception on the list my Psych teacher gave us in High School. The second semester I took my state-mandated health class, and what did my idiot of a teacher say about Schizophrenia? That the definition was "having multiple personalities." And the textbook defined it solely as "a serious mental disorder."

[SecondTalon]

Well, thanks, but did you carefully read my post?

Anfury?



I always love people who insist the Coriolis effect makes water in the sink/bathtub/toilet spin. Nevermind that those bodies of water are way the hell too small to be effected, nor that the designers of such devices know that spinning water drains faster than stagnant water, and design the drains and basins accordingly.

[peter]

You can kill someone by dropping a penny off the empire state building.

Woah woah woah. Seriously? I always thought it was possible.

[SecondTalon]

The terminal velocity of a penny is pretty low. I mean, a penny probably hits it's terminal velocity when chucked off the roof of a single story building.*

It'll sting, probably, but I doubt it'd even break skin.


*talking out my ass here.. probably a five-story building. Hell if I know, I just know it's going to hit it quick.

[miles01110]

The Theory of evolution. It's just a theory.

Haha, just kidding.

[cathrl]

Summer happens because the earth is closer to the sun in the summer.

Someone gave my ten year old a multiple choice pop science book in which this was given as the correct answer. I had a hell of a job convincing her otherwise, it was in a book, and therefore trumped anything Mummy said.

[rxninja]

The rubber in car tires is what protects you if lightning strikes your vehicle because it insulates against the electrical discharge.

The dispel: The car tires don't do shiat because you'd need a sheet of rubber a mile thick to insulate against the power of lightning. It's the fact that your car functions as a Faraday cage and Gauss's law (I think? The one that says a charge will stay on the same face of a functionally solid object) saves your ass.

They teach that one at the Boston Museum of Science during their awesome electricity presentations. I love that place so much.

[Geekthras]

Oh yeah. That scared the hell out of me as a kid.


On the moon, you'd just float away because there's no gravity, but the astronauts were wearing VERY heavy boots.


"The sky is blue because there's water in the air, and water is blue (look at the ocean!)."

/facepalm
The real reason is...

Spoiler:

Raleigh scattering. The sky acts as a prism for the sun's light and is actually purple. But we perceive it as blue. That's also why sunsets are red; light that travels at an angle almost tangent to the Earth's surface is bent more. Or less.


Keep in mind that this is all from about 8 years ago, so I'm a little fuzzy on the details.

[Khonsu]

Any of those tropes that begin with "[insert horrific natural disaster] tend to happen every [insert big number] years. It's been [big number] years since the last recorded [horrific natural disaster]. *TERSE MUSIC* " in specials on supposedly scientific, unbiased TV channels (Discovery, Science, History, and The Learning Channels--all owned by the same company). It's fearmongering bullshit, and I get enough of that from the news. All that super-volcano/epidemic/super-quake/super-meteor shit is so, so ridiculous. The probability is negligible, and honestly, it seems like The Powers That Be just like people to be afraid.

[theonemephisto]

Schizophrenia and Multiple Personality Disorder are the same thing.

It was the first misconception on the list my Psych teacher gave us in High School. The second semester I took my state-mandated health class, and what did my idiot of a teacher say about Schizophrenia? That the definition was "having multiple personalities." And the textbook defined it solely as "a serious mental disorder."

Yes, that annoys me so much. In just everyday conversation people constantly refer to anything resembling or reminding them of Multiple Personality Disorder as Schizophrenia, and I have to constantly correct it. I just don't understand where that misconception came from.

[ikerous]

If you want to be confused even more, try to guess the speed of electrons in typical wire. What? Nearly to c? Oh no, you are wrong - it is electomagnetic field which has such speed; electrons themselves move at velocity of several centimeters per second.

Electric force = Charge*Electric field = qE

W = int(F dr) = int (q E dr) = q int(E dr)

The integral of E dr is voltage. So W = qV. Assuming all the work goes into changing the electrons kinetic energy (And the voltage is 120 volts) then qV = 1/2 m v^2. so v = (2qV/m)^.5 or 6,400 Km/s

[prime]

"The sky is blue because there's water in the air, and water is blue (look at the ocean!)."

I couldn't believe what I was hearing last year when more than three people in my history class insisted that the sky was blue because light reflected off the ocean into the sky, coloring it blue.

Damn, I forgot about the huge mirror in the sky again!

Oh yeah, not really science, but two years ago someone mentioned "that tunnel that goes from New York to Paris under the Atlantic, it takes like 8 hours by train" and other people BACKED THEM UP (history class again).

[ATCG]

On the moon, you'd just float away because there's no gravity, but the astronauts were wearing VERY heavy boots.

Related and equally annoying: "Satellites stay in orbit and astronauts experience weightlessness because there is no gravity in space."

[stockpot]

Humans evolvd from apelike things. Chimpanzees are closely related to humans.... HUMANS EVOLVED FROM CHIMPANZEES!
Electron orbitals are just like planetary orbits, but the electrons are moving really, really fast!

[gmalivuk]

Humans evolvd from apelike things.

Well, we actually did evolve from (and technically are ourselves) apes, not apelike things.

The real misconception, though, is, as you said, that we evolved *from* chimps (or gorillas or modern monkeys or whatever). No. Those are our distant cousins, not our ancestors.

[Cheese]

Your mom is not fat. Haha, amusing misconception.

More widely (haha) held misconception, though: Rainbows are formed by the sun shining through raindrops, look, this lovely glass prism does the same thing!

[bigglesworth]

I always love people who insist the Coriolis effect makes water in the sink/bathtub/toilet spin. Nevermind that those bodies of water are way the hell too small to be effected, nor that the designers of such devices know that spinning water drains faster than stagnant water, and design the drains and basins accordingly.

You mean the nice Kenyan I paid five dollars to demonstrate that it spins one way in the northern hemisphere and the other in the southern hemisphere, and doesn't spin on the equator was fleecing me?

(Or since that's a silly question: was wrong?)

[Master Gunner]

Water is a good conductor of electricity.
While pretty much anything can conduct, it's the dissolved ions in water that allow for any serious flow.

[stockpot]

Humans evolvd from apelike things.

Well, we actually did evolve from (and technically are ourselves) apes, not apelike things.

True, but historically, we placed ourselves and our closest extinct relatives/ancestors in a seperate family from our fellow Great Apes, and most people still consider "ape" to mean only a member of one of the six-ish living species of gorillas, orangutans, and chimpanzees. That's mostly a labelling issue I was trying to avoid, though, and regardless of politics and cladistics, all apes, even us, really did evolve eventually from apelike things just as the distant anscestors of hamsters were not modern hamsters, but really rather hamsterlike things.

I do believe the most dangerous science misconception though, is "SCIENCE PROVES THINGS ARE TRUE." It does absolutely nothing of the sort.

[Cheese]

That's a good point. Science proves what isn't true, and makes good guesses based on that information of what IS true, at least in this universe with it's constants.

[cephalopod9]

I like the CG diagrams commercials have. Cleaning products are probably the best.

[xooll]

More widely (haha) held misconception, though: Rainbows are formed by the sun shining through raindrops, look, this lovely glass prism does the same thing!

Um. What's wrong with this?

[rxninja]

More widely (haha) held misconception, though: Rainbows are formed by the sun shining through raindrops, look, this lovely glass prism does the same thing!

Um. What's wrong with this?

The sun doesn't shine through raindrops, it actually refracts off of them at various angles. It is our perspective, relative to the refraction, that causes us to see a rainbow (aka: the full spectrum of light) based upon the various ways in which the light is bent. The prism-like effect is not from shining through, but shining into and reversing back out of, raindrops.

[TizzyFoe]

Airflow over a wing somehow "must" meet up at the trailing edge, so the faster flow over the longer top side causes lower pressure and thus lift. (Ugh. That's a common misconception even among first-year AE students.)

how does it actually work?

[Will]

They work by causing air to be pushed down behind the airfoil, which by newton's third law of motion, causes an upward force on the airfoil itself (lift.) The mass of the air being displaced has to be > the mass of the aircraft for this to work.

I read an article on the interwebs awhile ago tearing apart the nonsensical explanation that's given to practically every layman about how airfoils work, and suggesting a new explanation that basically boils down to the above paragraph. Note that I'm not an Aerospace Engineer, so a real one can probably (hopefully) provide a more detailed explanation than that.

[Hawknc]

No, that's the basic idea of it.

The reality is that an aerofoil has to be shaped so that there is a downward component of airflow behind the aerofoil, relative to the free stream. That means that the popular explanation, which requires an upper surface area to be larger than the lower surface area, CAN be right, but it's far from the only option. Diagrams help explain better than I can, though:

[EvanED]

That's a good point. Science proves what isn't true, and makes good guesses based on that information of what IS true, at least in this universe with it's constants.

To be a stickler for "truth", science doesn't prove what isn't true any more than it proves what is true. After all, if it proves that x isn't true, that is the same thing as proving that not x IS true, which you said it doesn't do.

[Geekthras]

Well yes but that doesn't help at all.
Ex.
p="The Sun revolves around the Earth"
q="The Earth revolves around Mars, which the Sun also revolves around."
r="The Earth revolves around the Sun."
p is false, so either q or r could be true. Or it could be that the Sun is a hallucination or that Xenu put it there for purposes unbeknownst to us.

Of course,that might be the point you're trying to make.

[EvanED]

Just for the record, I consider "the Earth revolves around the Sun" to be a scientific fallacy too.

It's far more accurate to say "when discussing astronomical phenomenon, it is often far more convenient to do so from a frame of reference considering the Sun to be stationary and the Earth to be revolving around it than one in which the Earth is stationary and everything is moving around us", but one of the key points of Einstein's theories (which people seem to conveniently ignore a lot) is that any frame of reference is as valid as any other frame of reference.

If a cop pulled you over and tried to give you a ticket for going 67,000 mph (which is over the posted limit of 25 mph) because you were traveling around the sun, I have a suspicion said ticket might not stand up in court.

[Twasbrillig]

In our isolated solar system, the Earth revolves around the Sun. Happy?

"Water is a renewable resource."

No it fucking isn't. You can't make water (shut up chemists, you can't say gold is renewable because there is an extremely long and complicated process - we're talking easily renewed quickly), you just reuse it. When I drink a glass of water, it goes, for all intents and purposes, through me. The whiz that comes out the other end is still the same water. By filtering it, you aren't renewing it, you're just taking out some of the bits you don't like. Grr.

[wing]

No, that's the basic idea of it.

The reality is that an aerofoil has to be shaped so that there is a downward component of airflow behind the aerofoil, relative to the free stream. That means that the popular explanation, which requires an upper surface area to be larger than the lower surface area, CAN be right, but it's far from the only option. Diagrams help explain better than I can, though:

Exactly. Which is why the use of flaps creates additional lift despite TOTALLY breaking the cross-section diagram that every TV show and most physics books (!!!!) give. The cross-section diagram that people are given and told "this is a wing" is actually just a rather nice aerodynamic shape without any meaningful ability to do any flying.

The same idea applies to why the F-117 can still fly. It uses a perfectly valid airfoil design, but with all the curves straightened out. It doesn't make for the most stable design, but it's still flyable thanks to the avionics system. The layman's understanding is that the computer, somehow, bends the laws of physics to make something that produces no lift into something that produces lift.


Somehow, the entire world has gotten it into their heads that the wing of an aircraft produces some sort of vacuum above the wing, and that it is PULLED up, not that the wings are PUSHING down. I encourage anyone who still doesn't get it to take a flight on a rainy day sitting a few rows behind the wing (I had a great seat for this in Row 31 of a United 757) - pay close attention during takeoff. Not only will the wings flex ALARMINGLY far upwards (to the layman), but the water spray off the wing is a beautiful demonstrator. Better than any Discovery Channel show.

[EvanED]

In our isolated solar system, the Earth revolves around the Sun. Happy?

No, because it still doesn't; it's still just convenient to think that it does.

(I expanded my post substantially after initially making it; it's possible you saw the shorter version before I spelled out what I mean more clearly. )

"Water is a renewable resource."

No it fucking isn't. You can't make water (shut up chemists, you can't say gold is renewable because there is an extremely long and complicated process - we're talking easily renewed quickly), you just reuse it. When I drink a glass of water, it goes, for all intents and purposes, through me. The whiz that comes out the other end is still the same water. By filtering it, you aren't renewing it, you're just taking out some of the bits you don't like. Grr.

I would consider that renewing it.

You couldn't use it before, now you can.

[rxninja]

Some stuff about wings

Quoted for the irony of someone with the handle of "wing" talking about wings.


Another example of bad science: The idea that "permanent magnets" are indeed permanent. Even magnetic strength decays over time, last I checked.