Material Definition and 1000 Threads

Dear Physicists, I am currently thinking of a way of inducing a current in a conducting material by a magnetic field. I am not good at magnetism and electricity at all, but I think it should look like the picture below. By the way, the material in the middle does not move. Does anyone...

I was wondering how long it takes to heat up materials. And how long will they hold their energy? Say for like thermal energy storage, how long does it take to heat up molten salts or other substances with sunlight? I guess I could just use Q=mcT and divide by time and then solve for time...

H-field depends on core material of toroid? If I got this right, the H-field does not depend on the material it is applied on and is only determined by its sources (free currents). So, suppose that we have a toroidal coil and some undefined core. As far as the H-filed is concerned, it would...

It just happened to me. And it's immensely frustrating. Not to mention the difficulty of convincing professors that I understand the material well (certainly well enough to get more than a 3.5 in it) despite getting below a 3.0 on the course. Yes, I made mistakes. My first few weeks were...

I've searched high and low among the vast archives of the internet and have yet to find any kind of formula regarding the magnetic field strength of ferromagnetic material (i.e bar magnet... etc). Does anyone know what/if there is one? As is B(r)=...? Thanks

Hello, I'm struggling to understand the exact conceptual difference between a flexo electric and peizo electric material. I mean, they seem more or less the same. could anyone please help me understand?

Homework Statement Toluene is recovered from a mixture of toluene and nitrogen (containing 52 mol% toluene) by cooling the mixture at constant pressure of 1.2 bar to condense out some of the toluene. If the flow rate of the mixture into the condenser is 179 kmol h-1, determine the flowrate of...

Assuming atoms pack together as hard spheres , find the largest intenstihal atom that can fit in a BCC arrangement of iron atoms . Take the radius of the irom atoms as 1,21 Å . Carry out the same calculations for an FCC arrangment of iron atoms . On the basis of these caluclation would you...

Homework Statement Suppose an unknown semiconductor material has bandgap energy of .1 eV. Density of states for conduction and valence bands are both = 10^18cm^-3. If the material is doped with shallow donors (n-type) Nd=10^17cm^-3, what is electron and hole concentrations? Homework...

Homework Statement A linear magnetic material in the shape of a circular disk of radius R and thickness d (d<<R) has a uniform magnetization M parallel to its axis. Find B and H at the center of the disk Homework Equations The Attempt at a Solution As the magnetization is uniform...

I came into my engineering class this morning and our teacher showed us this strange material. He got the material from a student who recently went hiking. According to the student, he and his father went into the woods and started a fire in an old metal tire rim. They threw a bunch of old...

I am really struggling to get to grips with this question, ( struggling with material balance overall!) I can do dimple material balance however for things with a recycle stream or purge stream, really confuses me. I have the solution which I will post up, but I still don't get 'why' it...

hi, I am confused about how the vapor pressure affects the materials growth. Can someone comment on the following : If the vapor pressure of a precursor, let's say N, is high then it will be hard to grow a material containing N because it will be hard to incorporate it onto the substrate...

What is the ratio of graduates to job positions for graduates?

Homework Statement A cylinder with an open top is to be constructed with a predetermined volume of 1metre cube. the base of the cylinder is to be cut from a sqaure sheet of material, and the rest of the square sheet is to be discarded, find the dimension which minimize the material used...

Electric/magnetic field at point P in presence of dielectric/magnetic material. I want to confirm either the electric field at a point P in space in an \vec E_{ext} field with the presence of a dielectric material is the sum of the \vec E_{ext} and electric field \vec E_{p} from the...

Hi all, For a while now I have been searching for an electrically conductive material which is also UV transparent. Anyone here has come across such a material (solid or liquid) ? Thanks :)

I have been working on what I thought was an easy problem. This was a one hour quiz in which the whole class failed, the instructor decided to give it as a homework assignment instead. ------problem start--------- Considerable interest exists in the conversion of coal into liquid products...

Hello I have composed some figures for a flywheel system that would be used in a custom car and involve multiple flywheels. The vehicle would be use the flywheels for energy storage and recovery, and would be powered by electric engines placed on the drive axles. These flywheels would be...

I'm currently in IB SL Math (No HL here unfortunately), and I wish to learn more about contest-type mathematics as I have 3-4 contest here this year. Is there any books/materials that's useful for me? I have taken a look at this book: https://www.amazon.com/dp/0817645276/?tag=pfamazon01-20...

Homework Statement A sample consisting of potassium chlorate and an inert material is intensely heated. The weight loss observed is 20.0 %. What percentage of the sample is inert material? 2. The attempt at a solution I know when you heat potassium chlorate and another material, the...

I just want to verify that the dipole moment \vec{m} in the presence of external magnetic field \vec{B} will line up in the the same direction and parallel with the external field. This is according to the right hand rule that if magnetic field is the direction of the thumb, the current will...

Not sure if this belongs in this subforum or not...if not my apologies What does the conductivity of a material depend on: the energy/band gap of the material or the free electron density of the material? We were posed this question on an exam and I said the answer was the energy gap of the...

Homework Statement http://img641.imageshack.us/img641/1996/graphyw.png Homework Equations [PLAIN]http://img140.imageshack.us/img140/4379/5400ad3870194a9786484cb.gif [PLAIN][PLAIN]http://img17.imageshack.us/img17/2517/4bb673fefcbe473fa83e468.gif The Attempt at a Solution I...

I'm going to start working on developing thermoluminescence material by studying effects of impurities (at my university),, i need references as well as brief intuitive descriptions and things like that,, links to important papers on the subject will be appreciated as well.. thnx

I got A's in Intro Physics but after its now been a few years and I am reviewing this stuff so I will be better prepared. I am reading through an Intro Physics book but find that I have forgotten a lot of this stuff. I seemed to have retained a lot of the general ideas but am not doing...

I think it would be swell to have a sphere made of a clear, solid material that had the refractive index of air, because it would essentially be invisible. Is there anything even close to this?

I'm currently studying Agri. Mech. Eng but I need some help on this, I know roughly what to do but it's where to start: 1. Design a skimming boom for a biomass slurry transfer tank which can have a reach of 7.5m. Tool must attach to a "quick hitch" plate - factory spec for the loader is...

1. Homework Statement A substance has an isothermal compressibility k= (aT^3)/(P^2) and an expansivity B = (bT^2)/P where a and b are constants, T is temperature, P is pressure. Find the equation of state of the substance. 2. Homework Equations B= 1/v(dv/dT) (v is specific volume aka...

One of our teachers says that For two abjects of same material the following law must obeyd. i.e the ratios of their masses will be equal to the ration of their areas, wether this law works for objects of same shape or different? what is the name of this law? give me a link from which i...

Hello, I have a homework of implementing finite difference solution of Hamilton-Jacobi equation using Matlab. The instructor is using her own set of notes. I'm a bit lost in details of the formulation (basically I want to learn more about the concept of characteristic curves, the merits of using...

I'm dropping a sphere from a known height, and it enters a viscous fluid. I know the initial velocity as it enters the fluid, from there I need the velocity as it falls through the fluid (as a function of time). I know it should approach it's settling velocity (terminal velocity) and from...

Hey guys, How do I create my own material in workbench? The material that I need is not available in engineering data. I have all the material properties that I need, just having hard time figuring that out. Thanks in advance

I am working toward my B.S. in Physics and Chemistry with the hope that both disciplines will converge to a good platform for me to pursue material science. My university doesn't offer a curriculum for mat. sci. and I was advised to do both (if I could pull it off.) The advantage, thus far...

Homework Statement l is an infintesimal material element of length. show that: Dl/Dt = l dot grad u where l is a smallelement that exists in the velocity field u. Consider its position at time t and t+dt The Attempt at a Solution have l(x,t) where x is representing all...

Hi! I'm trying to model a vacuum pipe on Ansys. I've already modeled it using an isotropic material, assuming its a plane strain problem (infinate pipe), but now I want to use a laminate structure composed of an orthogonal material such as nomex (honeycomb) with a seal tight layer of Al or...

Anyone has backgroud on silicon material or VLSI engineering please sound off, I will pm you or please pm me advance. Thanks in advance.

So, a friend and I are writing the GRE physics in two months. We are both studying in Sweden where almost NOBODY ever writes the GRE, and none of my fellow students know what it is. There is therefore a great shortage of advice, experience, tips, standardized courses and material. Are...

Has anyone ever seen this stuff? In class the other day one of my professors moved the sliding chalkboards around to reveal the behind-most chalkboard. As he was writing/erasing you could see the board ripple suggesting it was made from a much thinner than normal chalkboard. I am getting sick...

Can you please provide some explanation for the following two questions? Or please provide some links. Thank you. 1.) How does a laser heat up a material? Does the material absorb a photon and the material's atom gets excited? - when the atom relaxes, it emit an energy equal to that of the...

Hi, I am developing a Ultrasound application where the sensor will be in contact with the skin but I can't use gel for accoustic coupling (or any liquid). Any ideas of materials (suppliers) for this purpose ? Thanks/Brgds Joao

Hi i want to study analytical mechanics. Should i read up on differential equations and linear algebra before starting on analytical mechanics? How about electromagnetism (beyond year 1 level)? Which is better to start, electromagnetism or analytical mechanics? And how about the math? Can...

Hi all, I'm attempting to get a feel for the different mechanical measures of a material, e.g., strength, toughness, stiffness, etc. I'm looking around, and I can't seem to figure out where a measure of stretchiness would fit in, that being how much a material will actually stretch or deform...

Unfortunately I have not been able to find anything reasonable online. I'd like an in depth all-inclusive explanation of IR transmitters and receivers, from a physical standpoint. I would also be glad to learn whatever else is included in the reading material, if anything. I have basic...

So i went to my first calc 2 class today, and i was lost =( i took calc 1 2 semesters ago and i don't remember anything (i got a B+ on calc 1) few students felt the same way, and ask the professor what to do, and his reply was "will you consider take calc1 again? Thats my best advise" But i...

You have 100 grams of radioactive material, how do i know the half life and the time i have 100 grams of material X. you do not know the half-life you do not know the time it started to decay what is its half-life/starting time? is this equation even solvable? if so, how?

Quantum theory says that the energy, E , (in eV) of a photon of wavelength λ is E = hc/eλ, where h is Planck's Constant, c is the velocity of light and e is the charge on an electron. Calculate the bandgap of a material which absorbs electrons shorter than 500nm.

A ray of light travels through a medium with an index of refraction n_{1} and strikes an layered medium such that the index of refraction is n_{2}=ky+1 where y is the depth of the medium and k is a constant. If it hits at an angle of \theta_{1} with respect to the normal, find the angle...

Eager young mind at work im trying to come up with a concept of a suit that you ware at work, the main purpose is to let you have in on (like a uniform) but with a different design and material i have done some research but let's face it unless there is a different browser out there that I am...

Hi everyone, Can anyone suggest a raw material that has the properties similar to steel and produce less noise when meshing with other part. I thought of polymers like Cast nylon, HDPE etc, but the issue is, it has to withstand a temp of around 200°C, during working condition. Thanks...