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In general, reflection and refraction happen when light passes from one medium to another. You can see this if you see your own reflection in a window. Now, as a light ray approaches the critical angle, not only does the refracted ray get closer to the surface, but the amount of light transmitted gets less and less. At the critical angle, the refracted ray ...


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If the light ray is normal to the surface, 100% of the light is transmitted. As the light ray bends, as in your part (b), a percentage of the light will be transmitted (refracted) and the remaining will be reflected (at the incidence angle). Very near the critical angle $\theta_c - d\theta$, likewise, some of the light will be transmitted (refracted almost ...


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Today we know that Collins is wrong. He appears to be unaware of Newton's finding, and of course, advances made after he wrote his book.


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Every time you look up "the" spherical mirror formula, it comes with a set of "where's". These define what each symbol stands for, and the sigh convention to use to distinguish the location of objects and images and the difference between concave and convex radii. You can find different-looking spherical mirror formulas, with (naturally) different sets ...


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You are correct, I think the picture is self explanatory.


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It is on a small scale the same as a mirage in a desert. A mirage is a naturally occurring optical phenomenon in which light rays are bent to produce a displaced image of distant objects or the sky. In contrast to a hallucination, a mirage is a real optical phenomenon that can be captured on camera, since light rays are actually refracted to form ...


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Your friend is correct. It's not specular, because that would mean it's a mirror, and you'd only see the image if you were at the angle of reflection. Further, a mirror does not act as an image plane, so you might have difficulty ( :-( ) perceiving the image. Basically you'd need another lens to re-image the source. The diffuse surface acts as an image ...


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Your tags suggest that you are already in the way of the answer. Being spherical waves, sound intensity decreases inversely proportional to distance squared. The speaker facing the walls focuses waves in your position, before their intensities decrease as much as they would if they are reflected in other walls of the room.


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The light that you can see in the air is actually light that has been reflected from particles in the air (dust, water vapour, etc.) towards your eyes. So when the beam is pointing away from you, some of that light will still bounce off those particles and come to you; this is what allows you to see the beam. However, when you look at the water, it acts more ...


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If the beam light or what you say as cone is above the water what you will see is the reflection of light from the lighthouse and not the beam, as you can see it produces a cone shaped light with the help of a parabolic shaped reflector it have or either it uses other type, the point is that the light is focused and under tha law of reflection for specular ...


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If you coat the inside, the metal will get hot and this heat will conduct into the building. If you coat the outside (assuming it remains clean…) you will never get hot to begin with. I think this means that case 2 will be better for you. I have often wondered about simply having a secondary roof with a standoff - in essence, a space where air can flow ...


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There's quite a lot to say about this, 18490. The tl;dr for Mythbusters fans is at the end. Most materials are somewhat transparent. This is why you often need two or three coats of paint on a wall. The light enters the material, travelling many microns before it is eventually absorbed or scattered back. The result is usually that most of the light is ...


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Good question. The key is to realize that a mirror-like surface send rays of light into your eyes directly from the source; they just bounce simply off of the mirror. What you see is the source, and the color of the source. Not so for a diffuse object. In this case light from the source hits the mirror and does not bounce directly into your eye. It ...


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You can think of super massive object like black holes which can bend light. Near the event Horizon you could get a 180 degree turn for light and thus see the earth back in time. But I do not think this is practically possible as earth is small and dark (compared to stars) and this layer would get compressed really thin as some small deviation in the ...


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We cannot multiply light by mere reflections, because the very definition of "reflection" means that the same light comes out. We can however multiply light by letting it pass through special materials which we "pumped" into a certain state, that's called Laser. And yes, a Laser design includes a sequence of reflections, but it is not the series of ...


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If you split the circularly polarised light up into two perpendicular polarisations with a $\pi/2$ phase lag between them. You are free to choose which unit vectors to represent these perpendicular polarisations - so choose one in the plane of incidence and one parallel to it. Upon reflection at the Brewster angle the component polarised in the plane of ...


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There are (at least) two ways to get at the Brewster angle. One is to consider little electric dipoles that are set oscillating by the incident light - as you mention and which I won't expand upon. Where I work, this is how we teach it in basic optics. Then in electromagnetism we adopt the other approach which is to use the Fresnel equations (Fresnel ...


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Just another perspective: Since the sphere is non-ergodic, your observation depends on your and the source locations inside the sphere. For ergodic shapes (ellipsoid, etc), you will see an evenly lit world.



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