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The Accurate Source To Find Quotes To Vsauce – Michael Stevens – What Color Is A Mirror?”
The Accurate Source To Find Quotes To Vsauce – Michael Stevens – What Color Is A Mirror?”
[Vsauce – Michael Stevens – What Color Is A Mirror?][Vsauce – Michael Stevens] Source: LYBIO.net
Hey, Vsauce – Michael, here and today we are going to talk about color. (Green, Green Green) GOLD on, let me just PINK this up. YELLOW? Michael ORANGE you going to come to the concert this evening? I RED about that. There gonna be a lot of PURPLE there. I didn’t TEAL you about the this earlier. Look I have to go BROWN town first, but I’ll be WHITE BLACK. Colors.
Did you know that the human eye can differentiate 10,000,000 million different colors.
But what color is a mirror?
[Vsauce – Michael Stevens]
You might say Silver because mirrors are often illustrated that way and to be sure they are made out of Silver or silvery things like aluminum. But a mirror in reality is whatever color you point it at.
In this green room the mirror is green.
And if you look inside a mirror it becomes “You-Colored”. And object is whatever color it doesn’t absorb. These sticky notes are Orange because when hit with typical white light, they absorb every other wave length of visible light except for Orange. Which they defuse into your eyeballs. But a perfect mirror reflects all (Specular and Diffuse Reflection) colors equally, so in a way, you can say that a mirror is White. Except a mirror doesn’t reflect colors in the same way a pigment does. A mirror reflects incoming light in a single out going direction – specular reflection. Not diffuse. This kind of reflection creates an image of the very thing in front of the mirror. So as bad astronomy jokes: “a mirror is more or a smart kind of white.”
[Message:[badastronomy.com/mad/1996/mirror.html]
What color is a mirror?
Now that is a question I never would have thought of!
First lets define what color is. What we call white light is actually made up of lots of different colors of light, literally all the colors of the rainbow. It has been known for hundreds of years that light can behave like a wave. You can think of it like a series of ripples, with a height to each ripple and a distance between the incoming ripples (called the wavelength). The color of light is determined by the wavelength: the long wavelengths make red light, somewhat shorter makes yellow, shorter even than that makes blue.
Suppose you are wearing a red shirt. That means that of all the colors of light hitting the shirt, they all get absorbed by the shirt except for red. The red light gets reflected by the shirt and into your eye. So the color of an object depends on what wavelengths of light it reflects. If it reflects all wavelengths, we say it is white. If it reflects none it is black.
A perfect mirror does actually reflect all light hitting it. So why doesn’t it look white? It’s because a mirror reflects light in a coherent manner; that is, the light is reflected back from the mirror depending on how the light came in. A white shirt just reflects light back everywhere in all directions. Even if red and blue light hit the shirt coming from the same direction, they may get scattered in different directions. A mirror, on the other hand, reflects the blue and red light in the same direction, and so the mirror actually builds an image of the source of the light.
So you can think of a mirror as being white, since it reflects all colors, but a smart kind of white. I guess you could say that a mirror is simply the color of whatever light source it sees!
There are many places on the web that talk about rainbows, mirrors and light. Here is a great site about rainbows and colors, which is a good place to get started. This site has some nifty diagrams about light as well.]
[Vsauce – Michael Stevens] Source: LYBIO.net
But wait a second. That is a perfect mirror. And we live in the real world where there are no perfect mirrors. Every mirror absorbs a little bit of light. Not enough that it matters – I mean – looks pretty clear to me –
[Virtual tunnels and green glass: The colors of common mirrors[dtic.mil/dtic/tr/fulltext/u2/a523782.pdf]
Raymond L. Lee, Jr.a)
Mathematics and Science Division, United States Naval Academy, Annapolis, Maryland 21402
Javier Hernandez-Andres
Departamento de Optica, Facultad de Ciencias, Universidad de Granada, Granada 18071, Spain
Received 10 February 2003; accepted 25 July 2003
When a pair of common second-surface plane mirrors face each other, repeated mirror-to-mirror
reflections form a virtual optical tunnel with some unusual properties. One property readily analyzed
in a student experiment is that the color of objects becomes darker and greener the deeper we look
into the mirror tunnel. This simple observation is both visually compelling and physically
instructive: measuring and modeling a tunnel’s colors requires students to blend colorimetry and
spectrophotometry with a knowledge of how complex refractive indices and the Fresnel equations
predict reflectance spectra of composite materials. © 2004 American Association of Physics Teachers.
DOI: 10.1119/1.1615524
I. INTRODUCTION
Across the centuries, mirrors have given us windows onto
unusual worlds. Some of these worlds are as familiar as they
are fundamentally odd: the one that lets us see our own face
or the one that shows us a transposed twin of the room in
which we stand. Yet the oddest mirror world may be the one
found between two plane mirrors that face each other. If
these mirrors are parallel or nearly so , then looking into
either of them brings us to the vertiginous edge of a visual
tunnel that seems to recede endlessly into the virtual dis-
tance.
We call this phenomenon of repeated mirror reflections a
mirror tunnel, and here we are interested in how one formed
by two common mirrors transforms the colors of reflected
objects. We deï¬ne common mirrors as inexpensive second-
surface plane mirrors such as those found in homes. Under-
standing these transformations can teach students not only
about geometrical optics and spectral transfer functions, but
also how knowing the complex refractive indices of the
metal backing and glass in such mirrors lets us predict their
reflectance spectra via the Fresnel equations.1 In a student
experiment, two especially instructive and surprising re-
sults are that common mirrors are not spectrally neutral re-
flectors, and their reflectance spectra depend on the absorb-
ing and reflecting properties of both the glass substrate and
its metal backing.
Because mirror tunnels are so visually compelling, we use
them as a pedagogical tool in this paper. In Sec. II we de-
scribe how to set up a mirror tunnel and observe its color
shifts, and in Sec. III we discuss the measured reflectance
spectra of some common mirrors and show how we use such
spectra to calculate the chromaticity trends seen in mirror
tunnels. In Sec. IV we use existing data on the complex
refractive indices of silver and soda–lime silica glasses in a
simple model that calculates the reflectance spectra and chro-
maticities for these mirrors. At a minimum, students should
already be familiar with the optical signiï¬cance of the mate-
rials’ absorption, reflection, and transmission spectra. For
deeper insights, they also should understand how such purely
physical properties are translated into the psychophysical
metric of colorimetry. A very readable introduction to the
colorimetric system of the Commission Internationale de
l’Eclairage CIE is given in Ref. 2.
53
Am. J. Phys. 72 1 , January 2004
http://aapt.org/ajp
II. THE MIRROR TUNNEL DEMONSTRATION
One well-designed mirror tunnel is seen in Granada,
Spain’s Science Museum.3 This virtual tunnel is produced
simply by placing two tall mirrors parallel to and facing each
other see Fig. 1 . Viewers look at one mirror through two
small holes in the back of the other mirror; the holes are
spaced to match the average distance between human eyes.
This viewing geometry avoids the problem that can occur if
the viewer’s head is between the two mirrors, where it can
block the angularly smallest, most interesting regions of the
mirror tunnel.
On looking through the eyeholes, one sees a long progres-
sion of ever-smaller reflected images of the two mirrors that
plunges into the virtual distance, thus giving the illusion of
an inï¬nite tunnel Fig. 2 . If the mirrors are not exactly par-
allel as is true in Fig. 2 , then the tunnel curves in the same
direction that the mirrors tilt toward each other.4 After relish-
ing the vertiginous thrill of this virtual tunnel, we ï¬nd an-
other, subtler feature: the farther we look into the tunnel, the
greener and darker its reflected objects appear. To track this
color and brightness shift in Fig. 2, we put a photographer’s
gray card at the base of one mirror. Although the card’s im-
age becomes progressively darker and more yellow–green
with successive reflections, no such shifts occur for distant
real objects seen by a single reflection in either mirror.
This simple observation lies at the heart of our paper, and
it begs the question that students must answer: why do re-
peated reflections change the mirror images’ color and
brightness? Geometrical optics is silent on this point, be-
cause it predicts only the images’ location and size. Thus, to
explain the brightness and color changes, we must consider
the physical optics of common mirrors. Because color de-
pends on spectral variability, we start by examining the spec-
tral reflectances and transmissivities of the metal and glass
used to make these mirrors.
III. MEASURED REFLECTANCE SPECTRA
AND COLORS OF COMMON MIRRORS
Common household mirrors have long been made by de-
positing a thin ï¬lm of crystalline silver on the rear surface of
float-process flat glass.5 This silver ï¬lm is optically thick
minimum thickness 10 m , and its rear surface is pro-
tected from oxidation and abrasion by successive ï¬lms of
© 2004 American Association of Physics Teachers]
[Vsauce – Michael Stevens] Source: LYBIO.net
– but when you take a look at the spectrum of light: reflected by a typical mirror, you will find that it best reflects light within the 510 nanometers range (510 nm). Which we perceive as Green light. So technically a mirror is a tiny, tiny, tiny bit green. You may have noticed this yourself, when investigating a Mirror Tunnel, this happens when two mirrors face each other. Reflecting the same scene back and forth and back and forth and back and forth with each new reflection a little bit more visual light is lost but Green least of all. That’s why the reflection way down the tunnel is dimmer and Greener. So maybe real world mirrors aren’t smart white. They are actually kind of Green. But we should talk about White.
[Spanish Guy]
In Spanish, “white” is Blanco.
[French Girl]
In French, “white” is BLANC.
[Vsauce – Michael Stevens] Source: LYBIO.net
And in English we have a word that comes from the same root. BLACK. Which is the opposite of White. How did that happen? Well it turns out that all of those words come from the same ancient Proto-Indo-European root word. bhleg. Which meant Shine. Burn. Flash. Some languages took it to mean, the brightness of the flash: WHITE. While others took it to mean: “What’s left behind.” The burned, black, darkness. If you have blue eyes, your eyes aren’t actually blue, in a sense that the molecules inside them are absorbing all of the wave lengths of the visible light and diffusing the Blue. No, no, no, instead, your eyes are blue for the same reason that the sky is blue; interference. In our sky, light encounters molecules of air and because of the size of those molecules, light of longer wave lengths can slip on by. But shorter wave lengths crash into the particles, like Blue light and scatter, which is why we see blue when we look at the sky away from the sun. Without the air molecules that space would be just Black. And when direct sunlight has to travel through a lot of air, almost all the colors get scattered out except for the longest wavelengths the RED. Which is what gives the sunrise and sunset their color. The iris of your eyeball contains a hazy layer where light can be scattered just like the sky, through a similar but slightly different process. (Tyndall scattering vs. Rayleigh scattering) shorter wavelengths are scattered more, making your eyes look blue. Unless of course you have some melon in that iris, in which case your eyes are going to be Green, Hazel or Brown. Enjoy those colors. And as always thanks for watching.
Vsauce.
Vsauce – Michael Stevens – What Color Is A Mirror? So as bad astronomy jokes: “a mirror is more or a smart kind of white.” Complete Full Transcript, Dialogue, Remarks, Saying, Quotes, Words And Text.
