everyday life - Why do sunbeams diverge even though the sun is …
2014年12月26日 · Consider this picture of sun beams streaming onto the valley through the clouds. Given that the valley is only (at a guess) 3km wide, with simple trigonometry and the angles of the beams, this gives the result that the position of the light source is being a few tens of km away at most.
How much and what kind of radiation passes through a cloud?
2016年7月6日 · It varies by type of cloud, thickness, altitude, angle of the sun and likely many other factors. As a generality, clouds block a part of visible, UV and IR light depending on a number of factors especially depth of the cloud. Some of the EM waves are absorbed, some reflected and others pass through.
Sunrays through clouds paradox - Physics Stack Exchange
2019年9月19日 · Since all sun rays have their origin at the sun, they must be pointing away from the sun radially. Both in 3D and in the image you take. Now, take your image, and extend the visible sun rays back towards their origin. You will notice that those extensions converge exactly where the sun happens to be in the image (if it's within the image).
How much and what kind of sunlight passes through a cloud?
2016年7月5日 · Now there a small clouds and big clouds so it should be some average. Is this true or is the amount of sunlight passing throug a cloud really much more depending on the size of clouds. Is it for instance on a totally cloudy day that only 30% is passing and on a nice summerday when a cloud comes by it is 90%.
What makes Sun's light travel as parallel beams towards earth?
2014年12月28日 · Sun's light appear to travel as parallel beams towards earth $_1$. Sun produces electromagnetic radiations through pp chain and other reactions in Photosphere $_2$. I don't see whether these reactions send photons in that neatly arranged parallel rays, or else any other effects make the rays have such parallel beautiful motion.
Does regular sky clouds stops the sun's ultraviolet rays?
2012年7月2日 · Clouds don't absorb light (much), they reflect and refract it, and this applies to uv light in the same way as visible light. So a 100% cloudy sky will block uv light in the same way it blocks visible light.
visible light - Looking at the sun through heavy fog, do invisible ...
2015年9月20日 · $\begingroup$ According to a dermatologist I once asked, clouds (and by extension, fog) only attenuate UV light by about 10%. Without seeing a graph of EMF attenuation by wavelength I don't know who I would believe. Of course, attenuation is not the only factor - scattering could reduce intensity from the sun while spreading it across a wider area.
Flat-Earthers Claim: Crepuscular Rays $\\implies$ the Sun is Close
2016年6月20日 · Consequently what you are seeing are not rays moving through the clouds, but rays that are scattered by small particles or dust below the clouds. The divergence of these rays it not because of the direction light is traveling from the sun. but the visual occurrence of the maximum on the scattering lobe.
Why sun rays are parallel not of stars? - Physics Stack Exchange
2021年5月15日 · But there is intrinsic angular dispersion in light rays as well. Light from a point source, like a distant star, is diverging, in that it goes in all directions. For an extended source like the sun, the light from any point on the source diverges, but there you also have light from many different parts of the Sun converging on any particular ...
Why does the Sun appear white through clouds?
2021年4月5日 · When you see the sun through clouds, you get to see its actual colour more faithfully than usual, both because (as Mark Bell wrote) Mie scattering doesn't have the colour-separating effect that Rayleigh scattering does, and because you then see it against a grey / white backdrop instead of against the blue sky.