Questions tagged [visible-light]
Questions related to the perception and measurement of light (primarily in the visible range), its mathematical description, the reproduction of colors by different means, color combinations, etc. Please use the tag [electromagnetic-radiation] if you want to refer to the general form of light.
5,152 questions
0 votes
1 answer
48 views
Why can't we see blue gas moving in the sky? (instead, we see uniform and stable color)
We all know that the sky is blue due to Rayleigh scattering. And also we know that the smoke from a cigarette looks blue(ish) due to this phenomenon. So, why do we see "uniform" and "...
11 votes
1 answer
2k views
Why doesn't the light slow down, even if it loses energy? [duplicate]
The speed of light is roughly 3*$10^{8}$ m/s. Why doesn't the speed change when it bounces off a mirror or gets absorbed by an electron? If you throw a ball in outer space, and it hits a wall, the ...
2 votes
1 answer
183 views
What does a rainbow look like in Saturn due to the rain of diamonds?
Research tells that there could be diamond hail rain in Saturn due to black cloud of soot. So is there any possibility that you could see a rainbow from there? Well, the black cloud of soot and ...
0 votes
1 answer
95 views
Why am I getting Intensity of light depends on its color? (considering wave nature) [closed]
In my physics lecture I was told that intensity of light is directly proportional to (amplitude)^2 * (frequency)^2 Now I have a question about it; if intensity depends on frequency squared, shouldn’t ...
- 19
-1 votes
3 answers
182 views
Is it possible to explain how electromagnetic waves propagate through a vacuum solely using classical physics? [closed]
I'm struggling to understand how electromagnetic waves are able to sustain through a vacuum without thinking of them as photons instead of waves. Am I right in thinking of the situation as the wave ...
- 191
7 votes
1 answer
377 views
Causes of reddish halo in the clouds around the moon
While walking in the evening, I have noticed strange reddish halo in the clouds around moon : What are root causes of this phenomena? I suppose it's not the same effect when we see reddish sky at the ...
- 17.4k
1 vote
1 answer
73 views
How does light in the observable universe behave for an observer falling into a black hole?
Everything is relative as Einstein has long ago discovered. The effects of relativity are especially apparent near the extreme spacetime curvature sources like black holes. For an outer observer, ...
- 11
1 vote
0 answers
57 views
How does the usual depiction of an electromagnetic wave fit with depictions as a water style wave? [closed]
For eg. in the 2 slit experiment the interference pattern is due to a wave like on the surface of water which spreads out radially, and this is the case even with one photon. How does the linear ...
- 11
2 votes
2 answers
111 views
How is this kind of rainbow formed?
Earlier, I saw this rainbow out of my window: Sorry for the meagre quality. As you can see, there is a primary rainbow, but directly attached below the primary rainbow, another, fainter and thinner ...
- 121
0 votes
0 answers
55 views
What is the relationship between a "single pulsed spherical wave of light," and the "sinuisoidal vacuum" E+M wave eqn. solutions?
This question is purely conceptual and has bugged me for awhile. When we construct the light cone, we often think about "sending out" a single spherical light wave, sourced by a single pulse ...
- 15
1 vote
1 answer
56 views
Shadow from Direct Sunlight Visibly Brighter When Viewed Through Polzarized Lens?
I searched this site for about 10-20 minutes using both Google and its built-in search. Wasn't able to find any question similar to this one. I've taken Physics 1+2 and an introduction to modern ...
- 11
3 votes
6 answers
783 views
Can you estimate the distance between a light projected on a wall and the flashlight that generates that light?
For example, let's say the flashlight has a circular lens with a diameter of 5 centimeters and the light projected onto the wall has an apparent diameter of 1 meter. Could you figure out the distance ...
- 181
3 votes
3 answers
576 views
Quantum vs classical behavior of monochromatic light
A polarized beam of monochromatic light in classical physics is described by something like $$E = \hat z \cos(kx-\omega t),\quad B =\hat z\times E.$$ What happens if we aim this beam to a highly ...
- 1,685
0 votes
3 answers
93 views
Superposition of light beams by $\pi$ phase differences [closed]
What happens if we prepare superposition of two monochrome sinusoidal beams of light which are exactly the same but have $\pi$ differences in their phases? getting nothing?! $$E_1+E_2 = A\cos(kx-\...
- 1,685
8 votes
3 answers
939 views
Why don't objects 'invert' when viewed through a very small aperture? [duplicate]
We have seen in textbooks that, in a pinhole camera, light rays intersect at the aperture and then 'invert' inside the camera. But when I tried to replicate this by viewing objects through tiny holes ...
