Tag: sunlight

Why do different sunglasses appear darker than others?

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Why do different sunglasses appear darker than others?

Polarizing sunglasses block half the light (stopping horizontally polarized light and passing only vertically polarized light). But sunglasses of all types contain chemicals that absorb light of both polarizations. The darkness of the sunglasses depends on which chemicals are used and how much of those chemicals they contain. Some sunglasses are also coated with thin metallic layers that reflect a fraction of the light that strikes them. These semi-transparent mirrors can change the transmission of the sunglasses dramatically so that those sunglasses may transmit 50% of the light or 0.01% of the light. The manufacturer can choose.

How does light create heat?

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How does light create heat?

Actually, some light is heat. Heat is the energy that flows from one object to another because of a difference in their temperatures. The sun is hotter than you are so that it sends heat toward you. Sunlight is heat; it is the sun’s heat being sent toward you as electromagnetic radiation. When it strikes the surface of your skin, this radiation is absorbed and becomes the more familiar form of heat: kinetic and potential energy in the atoms and molecules. From the surface of your skin, this heat flows inward to warm the rest of your body. Any material that absorbs light usually converts it to heat. The charged particles in that material move under the influence of the light’s electric field and these moving charged particles transfer their energy here and there as heat.

How does suntan lotion work to prevent ultraviolet rays from damaging your skin?

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How does suntan lotion work to prevent ultraviolet rays from damaging your skin?

Suntan lotion (or rather sunscreen) is a chemical whose molecules absorb ultraviolet light and turn its energy into heat. Like fluorescent compounds, these molecules absorb ultraviolet light strongly. But unlike fluorescent compounds, the sunscreen molecules do not reemit any light. They convert all of the ultraviolet light energy into heat, which does no damage to your skin.

Why do sunspots affect radio and TV reception?

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Why do sunspots affect radio and TV reception?

Although I do not really know very much about the connection between sunspots and radio reception, I believe that the problem lies in with the solar wind. The solar wind is a steady stream of electrically charged particles that is responsible for the aurora, among other things. Since charged particles that interact with the earth’s magnetic field accelerate, they emit radio waves. These waves should cause reception problems on earth. If anyone reading this knows otherwise or has more information, please let me know.

If white color has a reflection close to one, what role does shininess or dullne…

Lou Bloomfield Leave a comment

If white color has a reflection close to one, what role does shininess or dullness play?

Just because two materials both reflect all of the light that strikes them doesn’t mean that they look the same. When you send a flashlight beam at a white surface, you can see that reflected light from all directions. When you send the flashlight beam at a mirror surface, you can only see the reflected light from one particular angle. Both the white surface and the mirror surface reflect virtually all of the light that hits them. A shiny white surface is different from a dull white surface because a shiny white surface has a small amount of mirror character to it: you can see the whiteness from any direction but there is also a mirror aspect that you can only see from certain angles.

Why do you sometimes see a circular rainbow surrounding a light?

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Why do you sometimes see a circular rainbow surrounding a light?

It is most often caused by the bending of light by mist around the light or by flaws in the optical components through which you are viewing the light. Whenever light passes through a clear material, its path bends. In most cases, you only notice that the light is distorted by its passage through the material. But different colors (wavelengths) of light bend by slightly different amounts so that the colors of light sometimes appear to come from slightly different directions. That’s the origin of the rainbow you see.