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1
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1answer
26 views

How big would an object look at a certain distance?

I've tried looking this up and found that objects only appear smaller because of the curvature of the eye. For example: the flowers are the same size, but since the second flower is farther, angle ...
1
vote
1answer
93 views

Why do we see brown light?

While researching about lasers (it's my hobby), it suddenly hit me: there are lasers for every color of the visible spectrum, but there are no brown lasers. Brown isn't even on the rainbow. How is it ...
2
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4answers
95 views

Why do object appear smaller when it is further away?

This might have nothing to do with physics but why does the size of an object change when it is further away from me compared to when it is closer to me? Can someone perhaps explain this through an ...
-1
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2answers
207 views

Why do we (3 dimensional creatures) see in 2 spatial dimensions? [closed]

Why do us humans, as 3-dimensional (in terms of space) creatures, see everything in 2 dimensions? Is it because the surface of every 3-dimensional object is 2 dimensional? Or because light enters our ...
0
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4answers
157 views

Is the hard problem of consciousness an obstacle to finding a physical theory of everything? Why or why not?

I do not understand how, without understanding the mind and how (physical) neural interactions within the brain give rise to consciousness, one can have a definitive theory of everything. There will ...
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0answers
51 views

Does the rotation of the Earth affect time?

If the Earth were to spin from east to west instead of west to east, how would that affect time or our perception of it?
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3answers
238 views

Is purple in visible light?

This isn’t a duplicate. I read those pages, but those didn’t answer my questions. Please watch this. Does visible light consist of red, orange, yellow, green, cyan and blue? No purple? My definition ...
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5answers
135 views

About the perception of the flowing of time

The user John Rennie suggested I ask the following as a new question: If time is continuous why would the perception of time being continuous or flowing be an illusion?
2
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0answers
328 views

Is there such a thing as purple light? [duplicate]

This is a question as much about color perception as the physics of light. Since I have normal vision, without color blindness, I will draw on my experiences in formulating my question. I will add ...
0
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1answer
124 views

If we could not see, would we think that nothing can go faster than sound?

And if so, then why does everybody keep asserting nothing can go faster than light speed (I'm implicitly assuming there could be something which we do not observe, which goes faster than light)?
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3answers
151 views

The atom, solid or liquid? [closed]

Now I know what you may be thinking, "buddy, do you realize that the quality of solid or liquid is Made by the sum total of atoms in a thing therefore an atom can't be a solid or liquid??" This, good ...
0
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1answer
75 views

How can monitors display a sharp image, if light travels in all direction?

The question title might be a misnomer, help me improve it. My question is, from my understanding, a light travels in all direction from it's origin point. Also I assume that in the example of a ...
3
votes
1answer
126 views

Do we see objects as they really are or does our brain manipulates itself?

The apparent size of an object decreases with increase in distance that's why we see rails get closer as they get farther. We don't see the rails parallel throughout their length but converging. But ...
1
vote
2answers
50 views

Time, distance perception [duplicate]

If photons going c have no local time or distance 'perception' why isn't the same true for us as we're going c relative to them?
9
votes
2answers
546 views

Why does the sky suddenly look gray through this window?

I am looking to the windowed roof of my building, and I notice that the sky, which has few white clouds, sometimes looks completely gray, as if there was a huge cover of gray clouds, but there are ...
0
votes
1answer
178 views

How powerful would an explosion have to be for its effects to be felt worldwide?

If an explosion were to occur at any point on earth, how powerful would that explosion have to be for it to be audible or otherwise detectable by every person on the planet? Detection could mean ...
0
votes
2answers
128 views

Does Free Will Theorem imply that quantum mechanics plays crucial role in our brain’s functioning (consciousness)?

Is opposite statement of Free Will Theorem right: If elementary particles have a certain amount of free will, then so must we? Because to me elementary particles does have a bit of free will – quantum ...
2
votes
1answer
85 views

From where does the sound come from when two charged objects meet in real life?

I am sure all of us have played with rubbing things and producing static electricity and when I was charging my comb by rubbing it on my hair and watching it attracting a small piece of paper, I heard ...
0
votes
1answer
694 views

Why do objects of a given color appear white under light of that color?

Under light from the sun, a red object will scatter the red component of light, and absorb all others. Hence, the human eye perceives it as "red". White objects scatter all wavelengths of light. ...
9
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2answers
843 views

Why do we remember the past but not the future?

The question is sometimes referred to as the "psychological arrow of time" (Hawking, 1985). Here the past is understood as a moment or time when the entropy of the universe was lower, and contrarily ...
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votes
1answer
114 views

Why and how the Universe has (at least) 3 spatial dimensions [closed]

We are conscious to live in a 3 dimension universe. Maybe it has more than 3 spatial dimensions (like the 10 mentioned in the string/M-theory) but that is not my concern here. My question is the ...
0
votes
3answers
112 views

Am I accelerating in the fourth dimension (time)? [closed]

I have an intuitive feeling that I am accelerating in the fourth dimension. As we get older, we all perceive time moving faster. Are there any arguments or theories in physics which address this ...
2
votes
3answers
229 views

Why can colors be mixed? [duplicate]

We can combine colored light, creating other colors, at least in terms of visual perception. But how it the result physically "a different color" - if it is at all? Or is all this not a physical ...
3
votes
2answers
181 views

About our voice transferred into electrical signal

I know when we speak to the microphone, the pitch of our voice cause the vibration of magnet in the microphone, thus causing generation of different voltages of electrical signal. But my question is: ...
2
votes
3answers
294 views

Velocity measurement in relativistic perspectives

I understand the precepts of relativistic time dilation, but I'm looking to nail down the local perception of velocity in each frame. My question is threefold: Given two observers $A$ (rest frame) ...
1
vote
1answer
347 views

Will a sound composed of the frequencies 450Hz, 650Hz 850Hz have a clearly defined musical pitch? Why?

According to my lecturer, the perceived pitch of a sound composed of the following harmonics: 750Hz, 1000Hz, 1250Hz is equal to the fundamental frequency which is the highest common factor of the ...
1
vote
1answer
66 views

Explanation request for flashes of light [closed]

I have observed what I believe to be the same phenomenon on two occasions and wanted to ask for possible explanations. Both times, I saw flashes of whitish light, near the ceiling of a room. They ...
2
votes
2answers
110 views

Can we see refraction of light in the air with our eyes?

Can we see refraction of light in the air with our eyes? I am asking that because every night I see that the light in the street moving little is that because of change in the air? I do not mean ...
3
votes
1answer
198 views

How can one learn to visualize 4 dimensional spacetime?

I was watching Professor Leonard Susskind's lecture on Quantum Entanglements and he said that there are physicists and people who study physics, who 'rewire' themselves so they can visualize 4 ...
3
votes
2answers
178 views

Why does the colour wheel wrap around?

Red colour bares 430-480THz and Violet bares 670-750THz according to Wikipedia. What frequencies are the colours between red and violet? Will they be higher than red? or lower than violet? What ...
4
votes
3answers
238 views

Why does the point of intersection of two shadows look brighter?

When I sit in my garden during the day I always keep looking at the two intersecting shadows of two rods. It looks something like this: What I find weird about it is that at the point of ...
2
votes
1answer
50 views

Predicting the direction of sound incorrectly? [closed]

When i was sitting outside my house yesterday, I heard a strange sharp sound. I could not point out it's exact direction but apparently looked like coming from left but later my friend told me that an ...
0
votes
3answers
280 views

Is everyone seeing the same color as I see? [duplicate]

As the cone cells are different in numbers in people, how can we say that everyone is seeing the color as same? for example the color you are saying as red may be not the one i see as red..
5
votes
0answers
130 views

To what degree does guitar construction affects the vibration of the strings?

There's an old debate going on in the guitar community about how much does wood choice and body shape affect the sound of an electric guitar. No one denies that there's a difference acoustically (how ...
0
votes
1answer
294 views

Why we can only perceive 3 dimensions [closed]

What is the reason that we cannot perceive more than 3 dimensions with our senses?
0
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1answer
30 views

Does the strength of a smell depend on the volume or surface area of an agglomerate of material?

I just switched from Timberland to Adidas shoes, and noticed a horrible trait of the Adidas tread: instead of being composed of externally-protruding bumps like the Timberland, it is composed of ...
4
votes
1answer
97 views

Differences of waves in water and air

When one drops a pebble in a body of water, one can observe multiple waves emanating from the point the pebble came in contact with water. Be it because the water "jumps" up and comes back down, ...
1
vote
0answers
57 views

Is there any evidence that everyone sees colours the same way? [duplicate]

We all know that the sky is blue. Grass is green. Blood is red. But, how do we know that everyone sees these colours more or less the same? How does one know that my ...
1
vote
0answers
46 views

How does my screen look to a mantis shrimp? [duplicate]

As a human, I have one 3 color receptors that activate somewhere around the colors red, green, and blue. However, as this very cool infographic displays, a mantis shrimp has 16 different color ...
5
votes
2answers
265 views

Is the color wheel just an optical illusion? [duplicate]

As a kid, I was taught that that blue and yellow make green, yellow and red make orange, and red and blue make purple - forming the subtractive color wheel. As an adolescent I was taught that blue and ...
5
votes
1answer
417 views

Why does the visible light spectrum appear to be circular [duplicate]

I'm not sure if this is an acceptable place to ask this question, as it may have more to do with the biological workings of human eyes than with the physical properties of light, but I'd rather hear a ...
4
votes
3answers
2k views

Why we see upright images?

Since it's convex lens there in our eyes so image formed on our retina is inverted, so how come that we see upright images?
0
votes
1answer
463 views

Can a sound mathematical formula become a science theory?

Can a sound mathematical formula become a science theory if it is constructed using a pattern creation process from sense-data, applied to observations by an inductive mapping, in contrast to ...
1
vote
1answer
603 views

How can you test what color different people perceive? [closed]

If I would show someone a yellow object and ask them, "is this object yellow?" That person would say "yes". But I could never know if my perception of the color yellow is the same as that other ...
0
votes
3answers
2k views

If we had three eyes, would our visual perspective be fourth dimensional?

If one covers up one eye, then he loses depth perception (two dimensional perspective). When we uncover that eye, we can now see depth (three dimensional perspective). My question is if we had four ...
9
votes
3answers
13k views

What is the color of a mirror?

A mirror couldn't be white, as then you wouldn't be able to see your reflection so clearly. It wouldn't be transparent, as that then won't reflect. So what color is it?
2
votes
1answer
62 views

Observable universe does it account for farther away galaxies measure of the observable universe?

From our planet we can only see so far on any direction. If a galaxy farther out than ours had a planet would its view extend beyond our measurements?
0
votes
4answers
731 views

Why does a photograph of a face look like it is always watching you?

Imagine a photo that is taken of someone looking straight at the camera. Why when we look at the photo now from any direction it looks as if the person is looking straight at us?
3
votes
1answer
179 views

Why do beverages taste different based on how cold they are? [closed]

Why does temperature effect the taste of beverages? Specifically, how does the temperature for example mask certain tastes ie filtered vs unfiltered water taste very similar at colder temp and Is ...
2
votes
2answers
2k views

Do we see color with higher frequency first?

Out of the 7 colours of the rainbow, violet has the highest frequency and the smallest wavelength. Does this mean that our eye sees it first? If yes, then why? Does it travel at the same or higher ...