Material Definition and 1000 Threads

In electrostatics, for what I understand the when I have an electric field, the density of the energy stored in it is given by the following formula: $$W = \frac{1 }{2} E \cdot D$$But when there is some material permantent polarization the above formula fails to work. Is this correct? How can...

what is the best material to keep the fish fresh, longer, plastic or aluminium foil?

Hello, I wonder if anyone knows of a valve or material that would allow air to pass both ways but prevent water to pass one way. It will be on the end of a tube used for siphoning so that air can be blown in and suctioned out but if water is collected it is diverted away from the end of the...

Hello, I am working on a project for an EE class and am brushing back up on the basics of strain and stress. My question was to do with how strain works in a material and if it is constant throughout. Say for example you had a setup like this The change in resistance the strain gauge...

The question is from a friend of mine who is computer-incompetent; I am only computer literate on a daily-citizen level (can follow instructions from software but never learned to read or write code). Although I cannot sit down at his computer with him (he lives in the US, about 11000 km from...

Is it advisable to have a Material Science background if I would like to pursue a postgraduate research studies in advanced thin film technologies?

Hey, I’m kinda of in a crisis in my head here. I’m in the US to pursue my masters in mechanical engineering. After the introductory material science course, I believe I’ve got a greater interest towards materials than mechanical engineering. Would transferring to Material Science be a good...

What are some interesting topics in the field of material fracture and deformation? Maybe a newer area of research?

Where are the solid-state Physics and Material Sciences overlapping? which topics?

For making gears as light and strong as possible, what is the best material to use?

Is the posted program a program of Physics of Material Science ? Can anyone help>> https://www.uni-leipzig.de/fileadmin/user_upload/Physics_IPSP_BSc_27.04.17.pdf > https://www.uni-leipzig.de/fileadmin/user_upload/Physics_IPSP_MSc_28.04.17.pdf

Can there be alternative materials for Aquarium fish tank instead of glass? Example : Stainless steel, Aluminium Plastic, Concrete etc If yes, which materials can be evaluated?

I live in a small town and would like to make some observations today. However i don't have a solar aperture filter, i only have an eyepiece filter of which i do not trust. So is there any household items, materials i could use safely to save me from from ordering on the net and waiting...

Experts, I'm in need of a balloon to hold an RF antenna aloft, and that can have a light (LED) in it. For cost & safety, it appears Helium is the choice. But everything I'm reading says that He atoms are so tiny they pass (eventually) through traditional balloon materials quickly. There is a...

Howdy! Could anyone advise on some high friction material combination ? I can't disclose full details of the application, but basically two flat parts a pressed together and force is applied along the plane of the joint. The pieces are about 4 square in, the force applied about 100 psi...

Homework Statement This is the exercise 10.6 from Feynman lectures on Physics 2. Two coaxial pipes of radii a and b(a<b) are lowered vertically into an oil bath. If a voltage V is applied between the pipes, show that the oil rises a height H. Show that H=(V^2)(κ-1)ε_0/[ln(b/a)ρ(b^2-a^2)g] where...

I couldn't get a good explanation differentiating phase and grain.From what I understood, a collection of unit cells arranged in the same orientation is called grain.A collection of grains with similar structure is called phase.Is this interpretation right?

This is a thought experiment, and I am making it as simple as possible. It all takes place out in space. It is necessary to create something that is like a common nail with a large head. It is made of the most ridge material possible, something that is held together by the most potent force...

Does anyone know how this works? I hypothesize that the reason that the bullet shatters is that boron carbide is much harder than the copper of the bullet. Does anyone think that this may be made into a conventional armor design as some people are saying or is boron carbide too expensive for use...

What sort of materials or elements heat up really fast but also cool down fast as well? Thanks in advance

Hello guys, I received an admit to grad school for Mechanical Engineering, where my focus was initially Thermo-Fluids . I've also enquired about the Material Science department at the University(in the USA), and they are willing to let me transfer to the Material Science department provided I...

Dear All, I don't have well background on material science. I would like to measure heterogeneity of a species (shrimp). How can I do it easily? Sincerely

Would it be possible in theory to develop a material with very slow velocity factor to build dipoles immersed in a slow velocity factor gas in order to make much smaller HF antennas?

Homework Statement Identify the set of points satisfying ##1<\vert 2z-6\vert <2## such that ##z\in\Bbb{C}##. My pre-caculus is very rusty, so I am not sure if I am doing this correctly. Homework Equations ##x^2 +y^2= r^2## ##\forall z,z'\in\Bbb{C}, \vert zz'\vert =\vert z\vert\vert z'\vert##...

Homework Statement I have E as a material parameter. It is a modulus of Elasticity It is given as: 109/E = 80/psi I want to write E as a value with units psi. Homework EquationsThe Attempt at a Solution Is this correct? 1/E = 80*109/psi So psi/E = 80*109 So E = 1.25*10^7 psi

Hi, I am currently constructing a personal project, and I was wondering if anybody knew any thin material that was relatively light weight, cheap, and as strong as wood. I understand that carbon fiber exists, but this material is rather expensive. If anyone knows alternatives to using wood or...

Hi, Suppose I have a 1D material of length L, and I want to calculate the spontanious emission rate Γ at ressonance frequeny. From my understanding, when light passes in a material at ressonance frequency it gets absorved by an electron in the atom, and after a spontaneous emission time tspont...

Background I broke my rib a few years ago. It healed in a way that it sticks out a little past the end of my rib-cage. I want to learn to surf, but it is uncomfortable to lay on my stomach on the board because of the rib. I would like to make a pad to relieve pressure on the rib that sticks out...

hello every one can you help me in selecting the material to be used in the blade of cutting machine which will be used to cut galvanized sheet metal

Here is someone who advised me the best educational material for my MB6-894 exam, I need a progressive and suitable education material for my exam through which I can success my exam well.

Homework Statement A 4.80 kg piece of solid material is heated from 16.4C to 219C (3 s.f.) using 787 kJ of energy (3 s.f.). Assuming an efficiency of 0.383 for the heating process, and that the material does not melt, calculate the specific heat capacity of the material. Homework Equations...

We have a problem with mentioned machine when making tests at speed like below 250mm/min its ok but if we go over that speed machine throws out error its like that the machine hasnt got enough power and because there is not smooth working programm shut down test. If i do a speed ramp to go up...

What is the best site to learn physics concepts with lots of examples? some site which doesn't show up on google. Like i give example of cplusplus.com which has all topics of c++ programs. Is there some physics site like that? Like i am always confused with pulley,strings, tension problems.

Okay there's a lot to chow down here but I am at a standstill. Ultimately there are too many variables and unknowns but I need a framework. I am transferring over to ASU from a community college and have declared physics as my major. This is something I have planned on for a while because I am...

Working on a research project to develop a test standard for abrasion testing pressure washer hoses. Ideally this could be used on any sort of hose. We have a set procedure that has worked on a couple hoses that looks like this: .Weight applied is constant .Cycle speed is constant .Constant...

Homework Statement A furnace wall consists of three layers of material as shown below. The thermal conductivities are: Firebrick = 1.15 W m–1 K–1 Insulating brick = 0.17 W m–1 K–1 Ordinary brick = 0.62 W m–1 K–1 Calculate: (i) the thermal resistance of each layer (ii) the heat loss per...

Hello PF, I am currently pursuing my Masters in Physics with specialisation in material science. But I am interested in quantum mechanics and want to do PhD and then research in quantum mechanics. But in today's date is it good to go for theoretical physics rather than going for some...

Physicists Create Quantum Electronic Material Known As 'Kagome Metal' https://interestingengineering.com/physicists-create-quantum-electronic-material-known-as-kagome-metal

Good afternoon, I'm trying to search only based on bibliography or numerical and theoretical calculations the change of the thermal optical properties, namely the solar absorptivity, of a polyimide-based plastics (VESPEL SP-1) in space conditions (considering radiation, atomized oxygen atoms...

Hi PF According to IEC 60885-2 and IEC 60270 the acceptance criteria in partial discharge (PD) measurements on high voltage cable insulation state that PD level should be below (< 5 pC). The insulation material that is refereed to is often XLPE which is a sensitive insulation to PD. Other...

I would like some help to find some additional info on generalized functions, generalized limits. My aim is to understand the strict definition of delta dirac δ(τ).If you could provide a concise tutorial focusing on δ(τ) not the entire theory...it would be of great help. I am not a math...

Does anyone know of any material that's not as brittle as ceramic that can withstand high temperatures and is non-conductive? I'm talking abou a max temp of 800degC of heat radiating from a hot steel coil. Components will be inside of the coil for a short period of time but trying to prepare...

Why do fermions exchange bosons with each other?

I have a question regarding perlite; as far as I know perlite can be used as a dye absorbing material. After absorbing dye, what do people do with it? Dispose of it? Or is there a method to recover the used perlite? Thanks!

To sustain a near perfect vacuum around a computer, that had an outgoing link? Also how would you defuse the temperature and vacuum loss of the outgoing cable to the other circuits? thanks

Good day I've been the task of designing an electromagnet to remove ferrous material from ore mixture. I've calculated the flux density require to remove the particle from underneath a burden depth of 400mm; which is 792.7177 Gauss. (Force index is: 1.5710*10^6 G^2/m) However what I've been...

Hi... I'm making a "magnet case" for very strong magnets. I'm wondering about what non-magnetic material to use that will allow the MOST amount of magnetism to flow through? My obvious choices are stainless steel, aluminum, Lexan, or wood---- which of these non-magnetic materials will be the...

For the material used in a heater plate to generate heat for example, for a given amount of power (say 4.5 kw) does the higher resistance of the material mean it will produce a higher temperature? Or is it the other way around?

(This is a two part question.) Ok, so I have been trying to find what property of a material determines if it is a good conductor or not. I'm hoping to go beyond just if it can conduct electricity or not. One of the explanations I have found is the length of the band gap. Is this right or...