Materials Definition and 919 Threads

Hi everyone, I am currently a third year University Student in the UK and I'm in the midst of doing my dissertation. My dissertation topic (Effective methods of decreasing the thermal Conductivity of Housing Materials) requires that I produce several experiments to test and analyse a certain...

In wikipedia I found: If what I underlined is correct, it means that from one incident photon we will get at the other end countless similar photons, as the "shaken" charges radiate "their own electromagnetic wave" (photons, right?). This sounds like light amplification, but the explanation...

If an electron is divided into quasiparticles in a material, then at the contact between the two materials does the interaction only occur between holons, since they carry a charge?

I've read about light slowing materials, and I'm wondering if you could slow down light enough, could it be used to say store light from the sun during the day so solar panels could work at night? Or would it not work because the process of slowing light down gradually absorbs some of the...

It is commonly said that the speed of light when traveling inside materials is lower than that of light in vacuum, but I don't understand how this can be true. It is the same light traveling, so how can it act differently? Does light appear to be slower in materials because it is not following a...

I am about to graduate with a doctorate in a Materials Science & Engineer degree. I have the following experience: - Mechanical testing such as indentation and bend testing - X-ray/neutron diffraction characterization (in/ex situ)...

Hi all, I have been trying to read up on quantum foundations after being first introduced to it on this Perimeter Institute page: https://www.perimeterinstitute.ca/research/research-areas/quantum-foundations/more-quantum-foundations However, I have had difficulty finding notes and papers on...

chemical vapor deposition, Molecular beam epitaxy or magnetron sputtering What is the best way to bond GaAs to the intrinsic layer of a laser diode? I am planning on building a refactory oven on a concrete pad this summer once I clear of one side of my yard. There is just no way around it...

Hi, I'm an undergrad materials engineering student. I am thinking of studying all the way to a PhD as I'm interested on working in research. Right now I work with Semiconductors and I like the field a lot. However, considering what I'm studying, I want to know if it's a good Idea to look for a...

In the UK you would need good grades at A-levels (age 18) in maths, physics and chemistry to start a three year BSc or four year MEng in Materials science. Some universities offer an additional 1 year foundation course if you don't quite have the required grades or possibly a missing subject...

Hi help please You have decided to landscape your back garden, and have chosen to: place a border around your pond (A) replace the broken fence surrounding the garden and add a decorative trellis build a patio in section B spray your lawn with lawn food (it's looking a little patchy) You can...

I have tried this a couple of times but no successBefore you buy materials, you need to work out how much you will need. As such, you need to calculate the following: the circumference of the pond -A the perimeter of the garden the patio area -b the lawn area (minus pond area) the pond area- a...

Hello everyone ! I'm Hugo. I'm a french high school student. This year I've a project on new way to store electricity and their materials.I've done researches on super capacitors. But I've found only that "new way" to store electric energy. And for the material part, I don't know what I can...

I'm curious how thermochromatic paint is made that has many changing colors corresponding to different temperatures? Read that liquid crystals are used but they same as in LCD displays or it's somekind another chemical?

Today, I turned on an electric kettle for heating up some water, then I going to did something else. Since the cover of the kettle was lost, it didn't automatically stop when boils, and I forgot to turn off the kettle when boiled, then all the water vaporized at last and the kettle stopped...

I want also to build electrolysis based hydrogen generator or and water oxygenator/aerator. It's simple electrolysis device but requires special electrodes that are corrosion resistant or at least safe for human consumption. I seen that hydrogen bottles use platinum titanium electrodes. Platinum...

I've read that nuclear waste is stored in Olympic-sized swimming pools, but what is it about water that so effectively stops radiation? And apparently, this shielding effect of water is so powerful that one could literally stand right next to the pool (and according to some things I've read...

Hi everyone, I am new here, so please be kind if I make mistakes on this forum, I will try to learn fast. I need help in explaining the solution of one of the examples from Timoshenko's Strength of Materials book. The solution is provided in the book, but I did not get it, no matter at which...

I am 2nd year physics undergrad. Just want to study a bit about materials in my free time. I have no idea about engineering books. Please suggest some good books. Thanks.

Hello there. I'm a veteran science teacher at the middle and high school level. I've taught a few years of physics and am interested in moving towards engineering. I have looked at a number of available curricula like Project Lead the Way which require a significant investment in time and money...

Hello, My university is offering a couple of programs in Physics: Applied, Astro, Computational, and Material. So far, I liked Material and Applied in terms of getting early job opportunities. What advise do you guys have for me, before I make my mind for any of them? Thank you!

Glass allows visible light to pass through I would like to find a list of materials that allows lights of different EM spectrum to pass through, not just the above, Searched throughout google, couldn't find any!.

Homework Statement Can anyone advise if this is a satisfactory answer. I've had a run over it and it does seem rather bulky for the given question. The Attempt at a Solution Commercial and marketing: Polymers can be classified in a variety of different ways. The commercial market are...

Hello, Looking for some guidance for my son. He will be a senior in high school in the fall and will be applying to university programs in Ontario, Canada. He is leaning towards studying chemistry and/or physics. We (his parents) absolutely want him to follow his passions, but of course are...

hello dear physicists I will work in my thesis on 1D materials using DFT as a numerical method to find the properietes of these 1D materials I would be very happy if someone can help me with references (books, links, articles, vedios ...) that could help me to advance in my work Thank you

Hi I'm on to the last question for my HNC and having a nightmare trying to work out my best options! Any help would be greatly appreciated! The bracket show in figure 1 is to be used to mount an outboard motor onto the transom of a boat. a. suggest two appropriate materials which will require...

At the interface between: 1) conductor/conductor 2) conductor/semiconductor (or dielectric) 3) semiconductor/semiconductor (or dielectric/dielectric) What quantity should be continuous? Is it the electrochemical potential, only the chemical potential or is it the electric potential? Since they...

For an anisotropic material, is there any way to analytically determine the elements of the stiffness matrix? For orthotropic and isotropic materials, there are analytical expressions relating the stiffness matrix elements to the elastic modulus and poisson's ratio, but I do not believe this...

As I understand, viscosity characterizes the "resistance" of a material to "flow locally" as a function of the velocity of the material flow. Now my question is following, what are the physical mechanisms involved which make this "resistance" dependent on velocity of the material movement/flow...

I Had been given an assignment on electronic properties of materials in reduced dimension as mentioned above so I have been given another option to choose whether it to be a theoretical approach or experimental approach which one should I choose.

So I'm working on this project for a inflatable solar sail (so a spherical solar sail) and we are really only verifying the deployment of the sail in space (from a cubesat)...We are doing a mock PDR and I need to find info on the sail we'll be using. My job is to find an "off the shelf"...

Hi fellow forum-ers :), I have a test in about two weeks where i am going to be given a dtl or ttl circuit which i have to analyse and calculate its function. The professor said that the circuit given to us will always be a useful and existing one meaning he's going to give us some NAND, NOR or...

Hello, I am doing a high school EEI to investigate the impact that the material of a cup has on the temperature of water inside the cup when left outside in the sun. The cups I am using are: Glass Steel Plastic Paper Theoretically, if I poured the same amount of water into each of the cups...

Homework Statement Knowing the left lug is carrying 10,000 lbs, determine the loads P1 and P2 in the lugs on the opposite side of the pin. Homework Equations Force Balance (ΣF=0) Another equation needed The Attempt at a Solution 10000 = P1 + P2 This is where I need another equation to...

<<moved from a technical forum, no template>> Need a Solution ASAP!

Homework Statement Find reactions at ends and deflection at C Homework Equations RA + RE = 115kN ##\delta##Total = ##\sum## (PiLi)/(AiEi) The Attempt at a Solution RA + RE = 115kN Then apply superposition: (Get rid of RE) divide whole member into 4 elements and add. ##\delta##Total =...

Hello every one. Ferroelectric materials have spantaneous polarization but i read in many articles that these ceramics are polarized by applying an electric field. Why polarize ceramics that are already polarized ? Thanks.

Homework Statement In an electric circuit, consisting of copper wires with cross section area of Sc=5mm2 and a temperature of t=25C, a lead fuse is added melting when the copper wire temperature increases by Δt=25C. Find the cross section area of the lead fuse wire Sl=x. specific heat...

Homework Statement a) State the boundary conditions for the electric field strength E and electric flux density D at a planar interface separating two media with dielectric constants ε1 and ε2. b) A parallel plate capacitor with a plate separation d is filled with two layers of different...

A complete table of the ac susceptibility ## \chi_m ## of various ferromagnetic materials, where ## M=\chi_m H ##, is something that I have had trouble finding in a google of ferromagnetic materials. In what I have been able to come up with to date, there is quite a spread in the values of...

Acoustic impedance of material is defined by density multiply by the velocity of waves within the base material. My question is if i have a tubular or hollow part with a base material, does this count as a reduction of density compared to the base material of the tube or hollow part. Would the...

Why are materials whose yield stresses are highly strain-rate dependent more susceptible to brittle fracture than those materials whose yield stresses do not exhibit marked strain-rate dependence

What is it like to work as a materials engineer as a civilian with the Department of Defense?

Homework Statement Question C(ii) Homework Equations dQ/dt =-kA(dθ/dx) dQ/dt = (θ1-θ2)/ ((lx/kxAx)+ (ly/kyAy)) The Attempt at a Solution So the first time I tried at this question, I was using the second equation provided above,but when I check the answer, they put the area on the numerator...

I am putting together a hands on activity for ninth graders, which will include testing different materials to determine whether they are attracted to a magnet. I have collected fasteners (screws, nails, bolts), and surprised that the fasteners I purchased labeled "zinc" are attracted to the...

I have selected a topic for my research work which is "nanostructured materials for solar energy conversion" I have read many of articles, most of which are about Li batteries but I want to do something new. Anyone who's in this field suggests something new.:smile:

Homework Statement https://ibb.co/imui5b[/B] hey i need to calculate max normal stress at BC and max shear stress at b and c is my torque equation right? Homework EquationsThe Attempt at a Solution so i thought Σma=0 Cx*6+80*6+80*2=0 i ll find cx and then ΣFx=0 and ΣFy=0

Homework Statement Homework Equations G = Shear Stress/Shear Strain G = E/(2(1+n)) n being poissons ratio The Attempt at a Solution So I know the easiest way to solve is simply to manipulate the first equation a little bit >>> Shear Stress = G * Shear Strain >>> Shear Stress = P/A >>>> P...

Hi, I'm currently in my last year of undergrad and I'm wondering about which specialization I should pursue. I'm looking for career stability, I don't mind leaving academia I'd just like to employ what I study in school in my future career. So, to my questions 1) In terms of career stability...

For an assignment, we need to make a model house and need to insulate it to conserve heat. The best insulation will be picked as the winner and they are compared with an infrared thermal camera. So I thought if I could absorb the IR, it would look colder on the image therefore seeming like the...