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There are two questions.. 1. What is the concept of magnetic monopole here? 2. Why Maxwell's eqns remain unmodified? They are not elementary particles as anticipated by P.M.Dirac. But the concept comes from the non-zero divergence of magnetization field. In electrostatics when you have $\nabla\cdot \mathbf{P}$ (polarization vector) not equal to zero, you ...


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Magnet's energy doesn't go anywhere. It always stays $\frac{B^2}{2\mu}$ (in some conditions). So where does the work come from, the energy to pull metal to the magnet? If you put piece of iron, or better a wire with flowing current $j$, on distance $d$ from source of magnetic field $B$, then there will be force between two: $\vec F=\vec j \times \vec B(d)$ ...


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We take into account the inelastic interactions that take place between the respective type of particle and the material, i.e. interaction that can consume part of the energy of the radiation particle, and calculate the mean-free path of the respective type of particle in the material. In this calculus we also consider the density and the structure of the ...


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The definition of work function that I am using is: the minimum thermodynamic work (i.e. energy) needed to remove an electron from a solid to a point in the vacuum immediately outside the solid surface. This could be viewed in the context of the photoelectric effect, the minimum energy photon required, incident to a surface, to liberate an electron ...


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The poster above is incorrect: FCC metals do not have a ductile to brittle transition temperature and instead remain ductile at low temperatures. This is because the stress required to move dislocations is not strongly temperature-dependent in FCC metals, and thus failure occurs by plastic flow instead of crack propagation. In BCC metals, the stress ...


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I think the only 'general method' is trial and error. A good catalyst is not expensive is not used up at a high rate (e.g. by poisoning by side reaction) enables high rates of chemical production The physics of how catalysts work is that, of course, they are involved in the chemical reaction. They react with the starting materials and then enable the ...


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"Soft and squishy" is a bulk property. That's not due to either the polyurethane or the air fraction individually, but of the combination. However, at the scale of a knife's edge, that foam is in fact locally either air or polyurethane. Cutting the air bubbles is trivially easy, but that small fraction of polyurethane is actually quite tough. So, while ...


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There are no simple "mixing" rules for defining pretty much any aspect of the physics of composite materials. Materials science is not that simple: chemical bonding of the same elements is radically different in different combinations. I think adding a new object to running code through the Factory Pattern for each and every new material you need is a ...


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Tires are black as most manufacturers add carbon black to rubber to dramatically reduce wear and tear. You can buy colored tires though if you wish.


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Great answer found here: Ductile and Brittle Failure of Materials When a stress is applied to any object, it deforms, i.e., changes shape and/or size. This deformation is called elastic if the object returns to its original shape after the applied stress has been removed. Deformation that is permanent is called plastic deformation. All ...


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Perovskites is a huge family of compounds and different compounds have been explored for different properties.Some of the major parameters being surface adsorption,catalytic properties,effect of oxygen percentage on various properties. Perovskites are also widely studied with respect to their production environment as it can affect stoichiometry and thus can ...


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WSxM is free and does this sort of statistics using the "flood" tool.


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This is the line I have been working on, but using Male African Elephants, and Dinosaurs with " n " Elephant Volumes , where the surface gravity of the Earth is inversely proportional to the cube root of the n E.V. ( Elephant Volumes ). n is limited to less than or equal to 13.0 E.V. The number has been getting smaller over the last 252 million years, which ...



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