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4
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1answer
27 views

Alkali metal transparent to UV - is cesium (somewhat) transparent to visible blue light?

Most optics texts will mention that alkali metals can become transparent in the near ultraviolet in the sections on reflections from metals, plasma frequency, and electron density. I remembered this ...
-1
votes
0answers
20 views

What is the position of hydrogen in the periodic table? [migrated]

Hydrogen is not in the first group as it was before and it is now placed above the periodic table? So why is it still categorized as a metal in some books?
1
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0answers
20 views

What happens to metal when exposed to an electric current for an extended period of time?

I was wondering what happens to the actual metal (copper, aluminum, silver, gold) when electricity is ran through it for a long period of time. Say years like the wire in a house. Does the ...
-1
votes
2answers
66 views

What happens to gold under immense pressure? [closed]

What would happen to gold if you put it under immense atmospheric pressures? For example 2M atmospheres.
0
votes
0answers
15 views

Magnetism loss in temporary magnets

There are many types of methods and materials to create a temporary magnet out of a non-magnetic piece of metal such as iron,nickel ect..but what makes them temporary? Heat,a high velocity impact to ...
0
votes
2answers
56 views

If two pieces of the same type of metal touch in space, will they bond and be permanently stuck together? [duplicate]

Yesterday I was watching discovery channel, on a program they said that 'if two pieces of the same type of metal touch in space, they will be permanently stuck to each other.' Is it true..? If yes... ...
3
votes
1answer
33 views

What are the effects of compositional changes in a thermocouple's junction?

We use thermocouples (type B) to measure the temperature of metals (Fe, Ag, Pd, etc) in a furnace under pressure. We weld two thermocouple wires together using an arc welder. This junction then comes ...
1
vote
0answers
27 views

High pressure deformation of metals

Does copper undergo elastic recovery after being exposed to high pressures (above 30 GPa in a diamond anvil) at room temperature?
0
votes
2answers
48 views

Copper density modification

Can you increase the density of a material surface (metal) by surface treatment? For example commercial copper. If we take the ordinary OF copper (99.95%), I would expect not to have the tabulated 8....
0
votes
0answers
24 views

crystal lattice modification

Can the lattice of a copper with FCC structure be altered, even microscopically? Copper has 0.361 nm lattice constant but can it be altered by external force, say neutron impact?
1
vote
3answers
62 views

Is there a way to measure the thickness of a metallic plate of order of micrometers?

I have a $5 cm×5 cm×? \mu m$ copper plate. Where '$?$', the thickness of the plate, is really small (about 30um). Is there anyway using physics to calculate the thickness? Update: Sorry I forgot ...
3
votes
2answers
39 views

Why chromium is more brittle than iron at room temperature?

Why is chromium more brittle than iron? I understand that both of them are BCC at room temperature. Is it to do with the grain size, and why is it different between the two metals?
0
votes
0answers
10 views

How long is the surface migration length of adatoms deposited by thermal evaporation in vacuum?

The deposition of metals through thermal evaporation involves the process of adatoms migrating on the substrate before its kinetic energy decreases to a certain point or before encountering a cluster. ...
0
votes
1answer
44 views

Electric current in metal objects

This might be a stupid question, but I can't find the answer anywhere. Why don't objects such as rings that people wear (which are made out of metal) have electric current in them? As far as I know ...
0
votes
0answers
44 views

Why does thicker aluminum do better at reflecting wifi

I have performed a experiment based one the ability of aluminium reflecting wifi radio waves. I have found out that the more aluminium foil i put on my reflector, the better result I can get. I did up ...
0
votes
1answer
36 views

Is it possible to levitate large objects through diamagnetic levitation?

I am currently building a diamagnetic levitator with a strong neodymium magnet, two slabs of bismuth (a diamagnetic material), and a small neodymium cube to levitate. However, I was wondering if it ...
1
vote
1answer
99 views

What is the desest material on earth? [closed]

Apart from the elements, do we know of materials that are denser? I.e. can an alloy be denser than the sum of its compounds, for example if the new lattice packs denser than each of the compounds it's ...
1
vote
1answer
27 views

What determines photoelectric yield

Is there any difference between the photoelectric yield of different metals apart from the threshold wavelength? To be more clear: Will metals with the same work function emit the same amount of ...
0
votes
1answer
43 views

Photoelectric effect on charged plate

As far as I know, to observe the photoelectric effect, one has to expose a metal surface to high-energy radiation. But what happens if the surface has a surplus of electrons? What is the energy needed ...
3
votes
1answer
51 views

Is the photoelectric effect 'Ionising Radiation'?

According to the definition on Wikipedia, ionising radiation is radiation which has sufficient energy to remove an electron from an atom. So a high energy gamma ray is definitely ionising, but visible ...
1
vote
0answers
10 views

Hopping integral for Hydrogen chain

When calculating a hydrogen chain in the tight binding approx., one comes across the hopping integral: $<m+1|V_{m+1}|m>$ Where $|m>$ is the 1s-Wavefunction at position m and $V_m$ is the ...
0
votes
1answer
52 views

How to reduce size of bracelets using physics?

My mom has a set of bangles (bracelets) made of gold like the ones shown in the picture. Problem is the size (diameter) of these bangles is a bit more than required. If she goes to a goldsmith he cuts ...
3
votes
2answers
60 views

Why are metals worse conductors when heated?

When metals, (such as in circuits), are heated, their ability to conduct electric current is hampered. Why is this? Does the transition towards liquid disrupt a metal's ability to conduct, or is ...
0
votes
0answers
30 views

How can a metal and an insulator have high dielectrics yet one is conducting and one is insulating?

I don't get it: insulators are referred to as dielectrics. The higher the dielectric the higher the insulation(?). But the dielectric constant of metals is considered infinite. Aren't they supposed to ...
6
votes
1answer
61 views

What happens at the point of welding iron?

What is the physics behind welding iron? It is obviously the electricity that causes the two metal parts to fuse but what is the role of the welding rod and why is it said to damage your eyes when you ...
1
vote
0answers
9 views

Effective interaction between electron-magnon in ferromagnetic transition metals

I wonder whether there are classical references on an effective theory of electron-magnon interaction in itinerant ferromagnetic metals?
2
votes
1answer
36 views

When electrons absorb energy and get excited then jump to a higher energy level do they do so in steps or do it directly?

So I was reading about Fermi surfaces. One of the first things that is obvious is that energy excitations happen at the boundary of the surface as the electrons deeper inside the surface do not have ...
1
vote
1answer
28 views

Find the spectral distribution of a metallic reflection given electron configuration

If I have the electron configuration for a metallic element, how do I find the spectral distribution of its specular reflection? For example, for gold (2,8,18,32,18,1) I should get a greater ...
0
votes
1answer
80 views

How is work function related to oxidation?

Low work function metals, such as Li and K, oxidize in ambient conditions, whereas high work function metals such as Au do not oxidize. In chemistry there's activation energy and reaction rate ...
1
vote
1answer
31 views

Are all FCC structures ductile?

Doing research on crystal structures and the effects of Ductile to Brittle transition at different temperatures. Results of this test proved aluminium to be a brittle structure, which I know to be ...
0
votes
1answer
22 views

Estimating fraction of radiant energy absorbed by a metal

I have a couple of texts on thermodynamics and radiant energy but am finding it difficult to figure out from these how energy absorption and reflection work. The area of interest is heating ferrous ...
0
votes
2answers
98 views

How to attract liquid metal with magnets

I would like to know if there is any way that I could make mercury or another liquid metal be attracted or repelled by magnets. Absolutely any solution would be okay with me. For example... can I ...
0
votes
0answers
71 views

absorption spectrum of aluminum

I am trying to find the absorption spectrum of aluminum but only can find reflectivity of it and other optical properties. It is easy to find absorption of aluminum oxide, foams etc. but not possible ...
0
votes
0answers
84 views

Model of the nucleus as fermi gas

I am taking an introductory course in modern physics, and am reviewing some of the exams from previous years. In our course, we studies the Fermi gas model for electrons in a metal. In one of the ...
1
vote
1answer
52 views

Can a magnetic field weaken aluminum?

I'm wondering if there is any reason to suspect that applying a magnetic field to a piece of solid aluminum would weaken it structurally in any way. The application is that I would like to put a stir ...
3
votes
1answer
82 views

What happens to the electron density in a metal during an electric discharge?

Suppose we are able to see into a grain of metal at the boundary between the grain and air (perhaps along one of the faces of this cube): (Source: Wikimedia Commons.) This image does not show the ...
2
votes
0answers
176 views

Could a falling office tower cause the melting of its iron or steel support structure? [closed]

Discussion on META: Questions related to geopolitical events Suppose you have an office tower, weighing around 300,000 metric tons, and has a height of ...
2
votes
0answers
88 views

What is “Accumulated plastic strain rate” in Current yield Norton law?

I'm doing FEA of steel under high strain rates and using Elasto-ViscoPlastic material model, with Von-mises yield criterion along with Isotropic hardening. The strain rate sensitivity is addressed by ...
0
votes
0answers
20 views

Are magnets attracted to mu-metal?

Are magnets attracted to mu-metal? Be aware that when watching videos of mu-metal they may have metals that are attached to the mu-metal and are attacted to magnets. Please don't get them confused.
0
votes
1answer
58 views

Can a magnetic ball “diffract” around a metal object?

Consider a magnetic ball falling through a copper pipe. It falls slower than it would if it wasn't near any copper. We can use this to determine that the closer a magnetic ball is to copper, the ...
2
votes
0answers
50 views

What kind of cheap, available, magnetic metal could I use for my boardgame? [closed]

My question revolves around my need to snap plaster walls to plaster dungeon floors for a boardgame called Dungeons & Dragons. My intention is to glue and paint over metallic strips under the ...
0
votes
0answers
11 views

Is it posssible to numerically simulate a metal layer the same way as a semiconductor one

I need to simulate a schottky junction device. Unfortunately, the software for simulation (AFORS-HET) doesn't allow adding metal (I need to simulate aluminum contact) layers (but it allows to add "MS-...
0
votes
2answers
36 views

Enhancing of EM waves through a materal or waveguide

I'm wondering whether there are materials for which an incident EM wave would behave as $\vec E(z,t)=\vec E_0 e^{\kappa z}e^{i(kz-\omega t)}$ where z describes how far from the surface the fields are ...
0
votes
1answer
13 views

Passive cathodic protection

Trying to understand what is happening when we need protect peace of Fe by placing on it more active metal (for example Zn) like ...
0
votes
1answer
144 views

Magnetization of soft iron and steel

I was reading and I saw that the steel becomes permanent magnet whereas iron becomes a temporary magnet after magnetization during magnetic induction. Why does soft iron make temporary magnets and ...
0
votes
1answer
114 views

crystal structure of metals

I am studying solid state physics and I'm a complete newbie in that sense. I know that semiconductors and group IV elements bond themselves in the FCC structure with covalent bonds which satiate the ...
2
votes
2answers
95 views

Do metals *really* conduct at zero temperature?

The questions is mostly in the title, but might expose another of my misunderstanding of the band structure of solids and how that leads to metals and insulators. If we have a solid, and the fermi ...
2
votes
2answers
138 views

Why doesn't dielectric materials have coloured reflections like conductors?

I'm a 3D artist trying to learn the basic (or perhaps even intermediate) level of physics of photorealistic rendering. But most artist and tutorials on the internet have little to no clue of the ...
0
votes
1answer
451 views

How quickly does a small piece of molten steel cool at room temperatures?

Say I have a $(\frac{1}{2}D)^2 \pi \times \ell = (.05)^2 \pi \times .03 \approx 0.000236 \ \text{mm}^3$ piece of molten steel freshly spewed out of a hot nozzle. Now assuming the nozzle moves away ...
0
votes
0answers
35 views

Why can we treat (most) metals classically at room temperature?

When we consider how light and metals interact with each other at room temperature, the Drude model, which is a classical theory, is usually and successfully used. My lecturer explained something ...