Material Definition and 1000 Threads

(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...

I’m working on an idea that I have, and I was wondering if there was something that could repel hydrogen. Not water, not oxygen, just hydrogen. Thanks!

I tested it by heating it up for 2 min on a electric stove and pour about 200 to 300 ml water in bowl and did a very quick dip in and out like that and when i touch it, it was cold same temperature as the water. I also test with aluminium but when I touch it, it was will hot I burnt my finger...

We know that belt drives are limited in their max possible power rating and most high power/torque applications(trucks) use gear drives. I wanted to know the main factor that limits the power/torque rating of belts. Is it Frictional slip or Belt material? If the frictional slip could be...

material A: E-modul:2000 yield stress:50MPa h_ET:99 h_h:200 vP:20 V epspkt:0.99 parameter used for material characteristic curve n building of material model - (linear elastic, elastic plastic and viscoplastic model) can someone explain to me what is h_ET, h_h, vP, V epspkt?

Hello all Currently struggle with a question from one of my assignments concerning poisons ratio . The notes given to me are vague and before i start trundling through the internet i was wondering if anyone could explain it ?

I want to make a stepper Motor. How to find the suitable core material. Can I use Annealed iron as core for stepper Motor? Will Eddy current loss will be more in it ? Is there any way to calculate diff core losses of diff material https://en.m.wikipedia.org/wiki/Magnetic_core Saw the following...

Hey! What do you guys think is the best modern looking material for a shock resistant phone case? I've been snooping around and stumbled upon a material called Carbon Nanotube, from the looks of things it looks quite ideal. What do you guys also think about Carbon Nanotubes? My idea is to...

Homework Statement Homework EquationsThe Attempt at a Solution Since the dependence of resistance upon the tem. is different for metal and semi - conductor ( increase of tem. decreases semi - con. resistivity while increases metal's resistivity.), option c is not the right answer. Since...

Problem I am designing a force sensing system with piezoelectric force sensors to determine the impact force on an object during a collision. The sensor will be placed between an aluminum block and either a TPU or PLA 3D printed "cover". The cover will be 5cm thick...

< Mentor Note -- thread moved to HH from the technical physics forums, so no HH Template is shown >[/color] How to find volumeof irregular and porous material like sponge?

To anyone who has experience with the building material "staff" ( https://en.wikipedia.org/wiki/Staff_%28building_material%29 ): Can it actually be bent? How would staff differ from a modern fiber reinforced plaster?

Hello, Let's consider a capacitor simply made of two conductors with arbitrary shape in the vacuum (http://www.kshitij-iitjee.com/Study/Physics/Part4/Chapter26/3.jpg). Now, if I place a small piece of dielectric material (for example a tiny sphere of glass) between the two conductors, the...

Hi, could anyone tell me, if they have any ideas as to, what materials could be combined to produce a material with two characteristics- electrical conductivity of about 10 S/m and magnetic permeability of 7500. Thanks in advance.

HI, I have application where i need to lift metal plate, 3kg weight, ( 3mmX 15mm), 250degree.C hot, for the period of 1min and put it back. For lifting purpose i am using actuators. As i have no opportunity to make hole in plate i have to use magnet for lifting purpose. I got Electromagnet...

I procrastinated big time about getting some solar filter or solar film or something to make my camera capable of filming the Sun, and now I can't find anything. I tried buying replacement glass for welding masks, but even with 4 sheets of it stacked together, the Sun blasts right through it...

hello all i'm trying to modal a complex material with matrix of material X and small spherical inclusion of material Y, i would like to have the ability to control the density of the inclusions and the surface properties between the material. does anyone know about a guide for the situation...

Greetings, I’m currently in the critical stages of my career right now and I really want to chose the best career option out there which suits my strength. My strength is doing R&D and I prefer computers and design simulation software like Ansys,Matlab,AutoCAD.I love thermodynamics,fluid...

I was not sure where to post this question so if anyone has a better home for it please advise. I am trying calculate how much temperature a given mass is required to be heated to (oven setting) to reach a target temperature on the surface of a metal like copper. I also need to know this...

Does anyone know the tensile strength and other mechanical properties of reduced graphene oxide? I know that it has some similarities to both graphene and graphene oxide, but I can't find any data on its tensile strength.

I am wondering why the material thickness is not factored into calculating bolt shear strength in a joint. I know that it is used when calculating the strength of the material itself and its susceptibility to deformation and tear out but why not the bolt? When you cut a piece of cheese you use...

Hello all I need a high K material to cancel out E-field in some direction (induced by electromagnetism). This high K material (above 5000) must work in high frequencies above 10MHz. I did use the ceramics but there is no clue that it will work in that range of frequencies or not. I am really...

It must be light strong and inexpensive. This would be used to make staging furniture. So it is moved often.

Hi, All. Given a scenario of a closed volume of volatile liquid and it's associated vapor above boiling point (ex. butane in a can at room temp.) which is dispensed through some tube or line: Is there some filtering medium capable of ensuring that only vapor may pass through the line, producing...

Used as a boat buffer.

Last year in a Intro to Radiation Oncology lecture I was sitting in on, a physics professor at my school said that all a terrorist (or otherwise bad guy) would need to do to kill or at least harm a bunch of people is take a small amount of radioactive material and hide it somewhere in a desk. He...

Hello folks, Got a project I've been tasked with completing. We have a small meat locker, approximately 4' x 6', and I need to design and build an above-head rack system to hang hams and other meats on. (approximately 50 to 60 lbs each) Can anyone offer a good starting point for a food grade...

Hi, I'm working in a design team for the first time and I'm in charge of choosing a material for an application. I have the constraints, support a tensile load of 50 kg , and the objective which is minimize the weight. I'm using the concept of material indexes to find the best material for the...

Hello friends. If i have a dieletric material ( w/ a hole) and apply an uniform eletric field on it, the eletric field in the hole will stay null ? Peace.

I have this fundamental question about stress and strain. If we apply same Force on two different objects of same geometry in the same configurations, will they experience the same stress? If yes, then does it imply that stress is independent of the internal material properties?

Hi, I don't know much about science of spectrometry, but I am working on a project where i need to detect and differentiate between different types of material types, and I was just wondering if I can use an Spectrometer such as Desktop Spectrometry Kit v3 (...

Hi! Completely forgot about this great forum! I'm designing an electron spin resonance /electron paramagnetic resonance spectrometer, as an easier vacation from my diy NMR - while still utilizing much of the same setup. Issue is; I have an X-band (~12GHz) waveguide cavity in a magnet, and I...

Homework Statement Photons with momentum p= 7.88 x 10-18 strike a photoelectric material which is in the configuration shown in the figure. The cutoff voltage is measured to be Vstop= 1.75 V. What is the work function of the photoelectric material? Homework Equations p = Ephoton / c E0 = (c...

https://www.airforcetimes.com/articles/air-force-academy-cadet-creates-goo-that-stops-bullets Any thoughts on this?

HI Guys, I am getting an error in Ansys Maxwell that says Maxwell2d solver, process solver2d: Internal Solver Error: 'In the Material: M270-35A_12 , the SLOPE of the End Two Points in this BH curve is 56519.1, which is more than 2 times of Mu0; This may lead to a non-physical solution...

After taking a course on Solid State electronics, (and doing a bit of my own research into the matter) I've gained a little bit of knowledge in the area of band structures, and phonons/photons. My question is as follows: I know that photons with an energy greater than the band gap can cause...

Hi all, I'd like to know what is the most transparent material that;s waterproof, but not as brittle as glass. I want to put a "roofing" on a section in my balcony where I usually hang my clothes to dry and disinfect them under the sun, but I don't want to run all the way up everytime it rains...

Hi all So I took graduate level courses of QFT, Quantum Gauge theories and a course on standard model of particle physics. I struggled a lot but got decent grades, so why does it all still look greek to me? It's becoming very frustrating to read sentences like "the theory is invariant under an...

i am doing composite analysis in ansys acp. i am using nomex hneycomb as core sandwiched with 3k twill carbon fiber on each side. i am unable to understand properties that my manufacturer gave. these are lengthwise and widthwise but in ansys i have to enter properties in x y z direction. can...

The frequency of plasma already achieved ... in a study, is presented the resonance frequency in eV, how to obtain in Hz? Wo = 7eV

Would you explain what "mechanical expansion or compression of a material" is? It makes no sense to me I only know thermal expansion or compression. https://www.google.tl/patents/US5004946 Thank you.

Hi PF! When doing a force balance in fluid mechanics, ##\sum F = D_t(mV)##. This equation typically results to the Navier-Stokes equations. I'm reading a the following problem: For small particles at low velocities, the first (linear) term in Stokes’ drag law implies ##F = kV##, where ##k##...

Hey guys just classified some soil according to USCS. Came up with either SM or SC. Been searching for about an hour on them but haven't stumbled upon anything that states whether they are good as a fill material or not. Any ideas?

Hello! My question is: If you travel in a material at the same speed as the speed of light (I assumed this is possible due to the existence of Cherenkov radiation) you will see the light basically stationary so you see a constant electric field which means no magnetic field. But light has both...

I have a project for my softball team and I need a material, probably a plastic, that is stiff enough to stand vertically for 24-36", yet thin like a broom bristle and can take impact. I don't want to damage the bats or break the bristles! Any help is appreciated! Thanks

Hey there, my honours year thesis is on the design and analysis of a carbon fibre wheel for a Formula Student racecar. However, I am unable to obtain carbon fibre material properties to input into the Engineering Data section. I am required to specify the Youngs Modulus in the x, y and z...

I have known what Ornstein-Zernike equation is. I try to plug in the form as follow to the isotropic materials: Still, I cannot show the pair correlation function as follow. Can anyone know what I have missed?

I am unsure whether I am posting in the right place, but was hoping someone could help me out. I was wondering if anyone knows the shape of the material at the beginning of the manufacturing process of a stub axle, and how the shape will vary depending on the quantity of products being made...

I would like to know if their are any materials that would allow light to pass in only one direction, In electricity we have diode, which will allow electricity to pass in only one direction, in optics how do we reflect light from one side and allow light from the other side to pass through?

Hi, Can anyone help me in finding out a Diamagnetic or Paramagnetism or Ferromagnetism or any other metal which has following capabilities: 1- Should not be attractive towards magnet. 2- Should not allow magnetic fields to pass through inside. Thanks! THG