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Imagine two opposite charges very very close together In the tiny region between the charges the field goes from the positive charge to the negative charge. However to everyone far away the field is pointing more in the other direction because the closer charge exerts a stronger force. You can imagine the plane that separates the charges, everywhere on the ...


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The reason is simple: the convention is that the polarization vector goes from negative to positive, not the other way around.


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This is due to the fact that different colors of light refract through glass (or whatever your glasses are made of) at different angles. Plain white light contains all other colors within it. When a beam of white light hits your glasses at an angle the yellow/red and blue/violet light separate from the main beam due to their different energy levels ...


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Where was the Sun at the time? The sky is viewed through Rayleigh scattered light. Unpolarised light (or rather, the electric field in the electromagnetic radiation) from the Sun can be imagined to cause oscillations in the bound electrons of atoms and molecules in the atmosphere. These electrons then remit light as oscillating electric dipoles, with a ...


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To add to John Rennie's answer and Noldor130884's answer: a half wavelength waveplate will reverse the handedness of circularly polarized light. It's the same principle as converting linear to circularly polarized light although here you don't have the precise alignment problems (to convert linear to circularly polarized, you need to align the input light's ...


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The answer depends on how you need to polarize it. Many lasers output highly polarized light anyway. Usually this is linearly polarized. If you need linearly polarized light, you may only need to align your laser correctly. This alignment is usually this is done with an adjustable polarization rotator rather than by rotating the laser. If you need ...


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You're missing the very last step: averaging the intensity over time. Since there's a $t$ inside the argument of the sinusoid, the contribution of that term is zero. Averaging over time is always done in these kinds of problems, though often implicitly. For example, if you just have one slit, the electric field might be proportional to $\cos(\omega t)$, in ...


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Personally I find statements like "differently polarized beams don't interfere" to be imprecise, but I can understand where the writer is coming from. The interference of waves of like polarization (or of longitudinal waves) is characterized by differing average power at different points, including places where the average power is reduced from the value ...


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Polarization and (temporal) coherence/phase of a light wave are two different, yet completely unrelated concepts. So there is no deep connection. Polarization has to do with the fact that the electric field is a vector and hence has a direction. This applies to static fields as well, although one does not speak of polarization here, but merely just ...


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(1) I assume you are referring to a Polaroid sheet (specifically H-sheet), which is the most common form of dichroic polariser; that is, it linearly polarises light by selective absorption of the electric field component in certain directions. On the molecular scale, this phenomenon is a result of the alignment of polyvinyl alcohol (PVA) chains within the ...


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As you probably already know, reflective surfaces invert the handedness of a C-pol light. So one solution would basically put a source of light in front of you, and the other one at your back, so that it would be reflected more or less from the direction from which the first source radiates. About thin films, I could possibly think of something, but it ...


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I'm not sure I understand what is being asked for part (b), but I will just explain a little about Malus's law. Polarizing filters block all light except that which travels in a single direction, vertical or horizontal [see note below]. Unpolarized light contains both horizontal and vertical components, so the first polarizer blocks either all the ...



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