Material Definition and 1000 Threads

Hi, there are two material points with unitary mass that can move on a stright line. They are subject to a potential of mutual interaction V which depends on x and y and it's not symmetric, where x and y are the coordinates of the two points. I can choose in the istant 0 v1,v2,x and y. How...

In what case will a material not be magnetized by a field (magnetic) if it is a type of conductor? thanks for your help!

Hello, I've been trying to learn exactly how materials are specified, with particular reference to pipes and fittings, and I've come across some conflicting information and apparent confusion. The callouts I've been coming across have an ASTM #, grade #, amd sometimes a UNS#. For example...

Hi all I need some suggestions on what material to use, hope you guys can help me. It needs to be an electric isolator, as rigid and stiff as possible without being brittle. I must be able to drill holes into it and put some pressure on it without it cracking and it needs to be as durable in...

Homework Statement Three bars of metal are known to be brass iron and steel. A magnet was used to distinguish between them. (the metal bars are placed under the south pole of a bar magnet and are used to pick up tacks) Metal 1 picked up 10, metal 2 picked up 6 and metal 3 picked up 2...

I am hoping for some advice on materials to be used for insulating up to 70kV. I am doing some preliminary research for an application in the aviation industry, however I am not an engineer and need some guidance. I have looked at mica sheet, although to insulate against such high voltages it...

I’m not sure in what is the best way approach this topic in-order to stay within the forum guidelines but I hope I’ve done so. From the recent moderator actions, this topic it is too far removed from the philosophy of mathematics to be part of that thread. The basic question is whether existence...

Determine the number of vacancies per cm^3 needed for a BCC iron crystal to have a density of 7.87 g/cm^3. The lattice parameter of the iron is 2.866x10^-8 cm and the atomic weight of the iron is 55.847 g/mol. Given: Avogradro's number, N=6.022x10^23 atoms/mol Help please? i have no idea how...

What is the spin direction of the electrons through the ferromagnetic material? It will become parallel or antiparallel? I was confused because the scattering rate and conductivity both depend on the density of state at Fermi level. For ferromagnetic material, is it right to say that at the...

Hello, if I broke for example a piece of wood in two pieces I give the atoms enough force to separate in the break point with the others, so why putting the two pieces together and pressing them the atoms don't join again ? Thank you!

Hi. I want to study probability over the summer. The course I'm taking in the fall uses the Degroot and Schervish textbook. My friend took it last semester and agreed to sell it to me for cheap,a nd I left it at my apartment back at college over the summer. I'd like to know what's a good book...

Hi, i'm searching for a material with the following properties: - high stiffness - low thermal conductivity - temperature resistance up to 150°C (not getting too soft at 150°C) - no low friction coefficient (so no PTFE) - good fracture behaviour (so no glass, ceramic) - cheap I've...

My situation is i have a 10kg battery that is mounted on top of a plastic material. How would i exactly calculate the right thickness for the plastic to support the 10kg battery?

Say you have two conductors and there is a dielectric material between them (a capacitor with a dielectric). The field will the polarize the atoms in the dielectric in such away that the potential difference between the two conductors is weakened. Thus a capacitor with a dielectric between it's...

Hello :) I am a student searching for a way to preserve raw food without a fridge for an assignment. Thinking about the method in which you wrap your food and bury it to keep it fresh, I wondered if there is some material that resembles the characteristics of soil. Have you came across...

Hi everyone I have a problem to solve, I already simulated it with FEMM, but I wonder if it is possible to find an analytical solution. Let's say that there's a small coil (100 turns) around a pipe (2in diameter), the pipe is filled with air. This pipe is located inside a bigger pipe...

Need a rigid insulation material? I have a project that requires insulation sheets that are rigid and difficult to compress, about 1/8" thick. I was thinking about some type of ceramic material but can't find anything in that thickness. I'm not looking for some type of exotic material, just...

Every semester, whenever I begin to learn a new subject, that is, a more advanced class of the previous subject (i.e. algebra -> pre-calc -> calc -> diff eq, etc.) I forget a lot of the stuff I learned in the previous class when I'm learning the new content and constantly have to review all the...

Homework Statement This is one of the questions in my materials engineering assignment. 1. Thermal shock is the focus of this problem. Note that the resistance to thermal shock of a material, “R”, is defined here as the temperature change required causing fracture: (σc*λ*(1-v))/(α*E) Where...

Hi, this is my first post here on the forum although I've been following some other threads recently. I'm currently working on a thesis project with a colleague of mine in which we are engineering a night time pacifier. We are at the moment trying to find a way to make the shield of the...

My purpose is to learn physics, chemistry and biology.I don't want to have a PhD level knowledge in 3 days, but I do want to have a better understanding of how the world works and be able to do things myself.Not in 3 days of course, but I like short(depending on subject) and clear explanations...

I can't seem to find any answers on this...I'm experimenting with some electromagnet designs, but I'm not sure what the best bobbin, or end caps would be. I was thinking about using steel washers welded to the iron core since it would be the strongest, but I thought that may affect the EM field...

Homework Statement Consider z = -3x - y + 11 Find a unit vector perpendicular to the plane, and find a vector parallel to the plane. Homework Equations The Attempt at a Solution 1.) 0 = -3x - y + 11 - z -11 = - 3x - y - z Perpendicular vector is then: -3i -j -k...

A shaft of a total length L, connected via coupling C to the engine on the left-hand side, transfers the power P while rotating with n revolutions per second. A gear with pitch diameter D1 and thickness t1attached to the shaft at the distance Lg from the coupling C is in mesh with the driven...

In crystalline material, bands arise due to the interaction of electron waves with periodic potentials. Can anyone please explain the origin of energy bands in non-crystalline material..couldn't find relevant links on Google.

Hey guys I have a few questions to ask: 1.) Why are materials whose yield stresses are highly strain-rate dependent more susceptible to brittle fractures than those materials whose yield stresses do not exhibit marked strain-rate dependence? 2.) How would you define 'toughness' in the case...

By "bendable" I mean "you can run it through a pulley and it retains tension", and by "strong" I refer to tensile yield strength. Thanks in advance.

Homework Statement Basically I want to know what material (That I could easily access) would be great to minimize impulse in the following situation: A car is placed at the top of a ramp with some angle less than 45 degrees and at its front there is a tracker that measures the amount of...

Does anyone know of any electromagnetic core materials that either do not oxidize or who's magnetic and physical strength doesn't change much when it does oxidize? I need to make a room temperature electromagnet for hydrodynamic propulsion experiments. My first experiments used an air core but...

hey guys I'm currently a first year engineering student and am at the point in my undergrad where I need to choose which engineering field i would like to go to. I've narrowed my choices to electrical engineering, material engineering, and chemical engineering. Could you please point of the...

Dear all, Does anyone of you know the name of some materials that self-decompose in anaerobic conditions (spontaneus decay possibly) in a reasonable time? I'm researching a possible application for this kind of things. Thank you in advance, Regards, D.

Homework Statement How large proportion of wavefront's power penetrates dielectric material's surface in a perpendicular collision from air. The only parameter that I have is \varepsilon_r = 16 where \varepsilon_r is the relative permittivity.Homework Equations \varepsilon = \varepsilon_r...

Hi, from where can I download engineering material data for structural steel in range of temperature 20 deg C - 1600 deg C ( 68 F - 2912 F). I'm interested in Poission ratio, Young modulus, density, thermal coefficient of expansion, specific heat and thermal conductivity versus temperature.

Hi, I am currently working on creating a portable rollable ballerina flat which can be easily transported in a women's purse and utilized as a backup pair of shoes when pain resulting from wearing high heeled shoes occurs. The reason for my inquiry is I am looking for a material to use to...

Hello all I am trying to measure material displacement using measured thermal data.7 While the specimen is heated up, I want to measure how much it changes its length at particular points. Is this possible? If you have any further questions or suggestions please do not hesitate to...

For a rod magnet, how is the field inside the rod change if another piece of ferro magnetic material is being brought close to one end of the rod? Does the presence of ferro magnetic material increase the field strength inside the rod magnet?

IF a material say a ferromagnet is placed in a magnetic field Bo then there will be an additional field due to ferromagnet which is equal to uoM (M is magnetisation) My doubt is how is the additional field equal to uoM. By considering the units of both this expression is indeed equal to the...

Gauss's Law -- Insulating Material Homework Statement A slab of insulating material of uniform thickness d, lying between -{d}/{2} to +{d}/{2} along the x axis, extends infinitely in the y and z directions. The slab has a uniform charge density rho. The electric field is zero in the middle of...

I am beginner to General Theory of Relativity. Please do suggest any good books, so that I can learn on my own. Anyone, please... If the book is an Indian Edition its very fine.. Thanks in advance to all..

Where to find AP Physics C: Mechanics material? So I would like to write the AP Physics exam this year. Unfortunately, my school does not offer AP physics and therefore does not have any material I can look at. So I have gotten myself a textbook, sadly, it does not have much practice material...

Physical laws ... are they material?! There was an old question about physical laws , where do they come from? as they are considered separated from the material of the universe. Of course I know that they are produced by the human brain or human consciousness (which is material in turn) , but...

I have worked several different jobs, such as a mechanic for 7 years, logger for 4 years and a welder for 3 years. long stories for each, but i am mechanically inclined. Everywhere i have gone i have been able to look at different things and figure them out quickly, how to fix them and how they...

Hello everyone, I am trying to make a coil with the exact specs as the original. I have all the info I need except the actual core material used. I have all the measurements of the core and coil including: Wire gauge, # of turns and turns per layer,Bobbin dimensions, inductance without the...

Hi guys, 1st year mech engineering student looking to get some input on a recent project for my Material Selection class I have to select an alternative material that could be used to make a car piston For simplicity I'll only be forcusing on the piston itself, not the con rods or anything...

Homework Statement Consider a metal with an BCC crystal structure and atomic weight 92.91. When monochromatic x-radiation having a wavelength of 0.14 nm is used, the angle of diffraction (2*theta) for the (211) set of planes in this metal occurs at 41.148 ° (first-order reflection)...

Source. Can someone explain what this means? It seems like it would be a big deal if something that should be a conductor, wasn't. But the word "measured" gets me confused. I start think of quantum mechanics, and maybe I am right to do so, but not sure so just a clarification of what's...

Homework Statement I have a university project that involves comparing various paints with regards to how they affect the insulating properties of houses. As part of that I would like to measure the emissivity of the paint for a variety of wavelengths. Unfortunately I can not simply heat...

(A disclaimer: I'm not an expert, having genuine confusion) There is a high concentration of introductory material on wave-particle duality that claims that the uncertainty principle manifests itself identically to the behavior of waves in the macro world. This however appears to be in direct...

Thought this podcast may be of interest to you guys. It's from Boise State's (where I went to school and work with now) Beyond the Blue program, which is a podcast series that spotlights various academics from the university. This one is from Amy Moll, who is a professor of material science...

Homework Statement Beam of electrons (charged particles!) is directed to copper absorber with known energy (E= 10MeV) and intensity (10^8(s*cm^2)^-1) . I need to find the thickness of absorber so that all electrons would be absorbed. Also under what conditions does it happen and what is...