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Can a homogeneous solution really not be split by centrifuge?

The issue is that salt ions, while heavier than individual water molecules (they are after all an ion surrounded by coordinated molecules) are not much heavier, and the diffusion rate due to thermal ...
Anders Sandberg's user avatar
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Variations in Refractive Index of Materials

Refractive index defines the change in speed for propagating the light through the material relative to propagating the light in vacuum. $$ n \equiv \frac{c}{v}$$ Higher values indicate slower ...
Jeffrey J Weimer's user avatar
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Variations in Refractive Index of Materials

TL;DR Refractive index is determined by the way electrons interact with incoming electromagnetic waves. Impurity atoms in glass change the way they interact. Pure materials have principly known, ...
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Variations in Refractive Index of Materials

The refractive index of a material is closely related to its dielectric susceptibility tensor. Both are a function of the wavelength (or frequency or angular frequency, depending on how you prefer to ...
ondas's user avatar
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Variations in Refractive Index of Materials

Density of a substance doesn't determine it's optical density or refractive index. For example, kerosene oil has lower density that water (it floats on water) but has higher refractive index and is ...
Aditi's user avatar
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Does infrared radiation emitted by an object happen only from its surface, or is emission also from the centre of the object?

If an infrared photon is somehow generated inside a piece of metal it immediately smacks into a metal atom in the metallic lattice and its electromagnetic energy is converted into vibrational energy ...
niels nielsen's user avatar
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Does infrared radiation emitted by an object happen only from its surface, or is emission also from the centre of the object?

If you are analyzing an object that is opaque to infrared radiation (as most are), then any infrared radiation that is created inside would quickly run into a different part of the object and be ...
BowlOfRed's user avatar
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Does infrared radiation emitted by an object happen only from its surface, or is emission also from the centre of the object?

Blackbody radiation is emitted from both the surface and the insides of a body. An ideal blackbody has its surface temperature in thermal equilibrium with its insides, so one can think of it as ...
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Is natural frequency a local or global property?

In this answer, I'll first focus on non-damped systems, and later introduce damping with the modal damping assumption, common in structural mechanics. In this answer, let's assume: we're dealing with ...
basics's user avatar
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What is current density and is it a material property?

No, current density is not a property of the medium. It's not a property of the medium itself, but it can be related to some property of the medium, like resistivity $\sigma$, and to other ...
basics's user avatar
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3 votes
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Should natural frequency be modeled using molecules?

Normally, when we talk about molecules in a solid vibrating, we mean that the vibrating molecule is moving back and forth with respect to the lattice/its surrounding molecules. The amplitude of this ...
David_h's user avatar
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