All Questions
Tagged with optics visible-light
1,367
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Can the eye lens not produce a virtual image when the object is between Focus and Optical Centre?
My teacher dismissed the question saying it is not possible for the eye to do so simply because we didn't know the focal length of the eye. That confused me. The focal length can vary, sure. When we ...
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Specular and diffuse reflection at the same time
if we know that tomatoes absorb all the light and reflect the red diffusely, how can we see the reflection of all the light specularly at the shinnig point? there isnt an absorption of other colors at ...
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Does color temperature limit how much a laser of a given wavelength can heat a target?
The Sun has a peak wavelength of around 500 nm and an effective surface temperature of 5770 K, and sunlight cannot be focused to make something hotter than the Sun, because this would be heat flowing ...
- 151
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Solarization Spectrum
I'm looking to better understand the relation between the spectrum of the light which induces solarization in glass and the spectrum of the induced absorption.
More specifically, I'm interested in ...
- 1,538
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Directionality of laser light in vacuum [duplicate]
It is well-known that laser light is directional because of coherence from stimulated emission. This means that the light is emitted ONLY in the direction of propagation, and not in any type of ...
- 5,097
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What's at the end of a rainbow?
I recently saw a video where someone saw the end of a rainbow as it went into a lake. How is this even possible considering the fact that rainbows have no ends and are circular in nature?
Edit: I ...
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1
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Exit Pupil, Objective Aperture, Magnification, and Brightness
Why is it that for two pairs of binoculars, with equal aperture, the one with smaller magnification has larger exit pupil and results in brighter images? If I understand correctly, the aperture ...
- 97.9k
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Optics - Object between two ���parallel plane mirrors”
The problem is the question 5.67 of Hecht book - Optics
Suppose two mirrors (A and B) are 25 cm apart and a small candle is placed in between them such that you
cannot see it. You see the images at $...
CommunityBot
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Diffraction limit of light
What is the diffraction limit of light? I see the following explanation in many papers on plasmonics:
Light can be focused to dimensions no smaller than roughly half the wavelength
What is the ...
CommunityBot
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2
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2
answers
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Why do gaps in my blinds create multiple lines?
Multiple lines appear on my floor every morning from the gaps in my blinds.
Why does this happen and does it have to do with light being a wave, like in the double slit experiment? If so could it be ...
- 207k
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Can the rainbow illustrate the colors we can’t see? [duplicate]
Seen as how we’re only able to see a relatively small portion of the electromagnetic spectrum, does the rainbow “keep going” in the frequencies we cannot see?
In other words; if we were able to see ...
2
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1
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Will a combination lens have symmetric focal length on either side?
In this discussion on finding the focal length for combination lens, the image described in the answer shows the measure of focal lengths.
Description of the Gullstrand equation also talk about front ...
CommunityBot
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-4
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1
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Why does a ventilator appear to run leftwise and rightwise and back when spinning up?
My university professor, a friend of mine, asked me: "Do you know why, when a ventilator starts and during the process up to final speed, it runs clockwise and anticlockwise and back again to ...
- 49.9k
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9
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Why can't we see infrared light?
While explaining to my nephew about the physics of light, I told him we cannot see infrared color, and he kicked back with a very simple question: why can't we see it? I could not tell him. Is the ...
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Are human eyes the best possible camera?
I am not a physiologist, but whatever little I know about human eyes always makes me wonder by its details of optical subtleties. A question always comes to mind. Are human eyes the best possible ...
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