A material is a substance or mixture of substances that constitutes an object. Materials can be pure or impure, living or non-living matter. Materials can be classified based on their physical and chemical properties, or on their geological origin or biological function. Materials science is the study of materials and their applications.
Raw materials can be processed in different ways to influence their properties, by purification, shaping or the introduction of other materials. New materials can be produced from raw materials by synthesis.
In industry, materials are inputs to manufacturing processes to produce products or more complex materials.
I'm a math major, but I really want to learn about general relativity (the 'real' GR, not the watered-down version that gets into popular science books) on my own. I'm not in any rush to learn it--i.e., I'm willing to work through a big tome like Gravitation over the course of, say, the next...
Can Microwave radiation penetrates building materials? I'm living within 120 meters from a mobile phone base station and I'm concerned with possible health effects from it .
Hello Everyone,
I'm interested in designing my own custom electric motor for some experiments and I am trying to do some research on some of the various laminated steel materials available. I have a decent working knowledge of general magnetic material properties, saturation characteristics...
Hi everyone
I'm having a bit of trouble solving this question. If anyone can help that would be awesome
Homework Statement
Rank the materials in the diagram according to their refractive indices from greatest to smallest (see attachment)
The attempt at a solution
The greater the...
Homework Statement
Show that the polarization of a material is P=Nqx where x is the displacement between the center of the electron cloud and the atomic nucleus.
Homework Equations
P=Nqx is given and I went ahead and subbed (q/m) * E[1/(w0^2 - w^2)] for x.
The Attempt at a Solution...
Hi,
How can I measure the capacitance of a capacitor, using the following:
a battery,
a digital voltmeter (which records voltage as a function of time),
a digital ammeter (which records current as a function of time),
an industrial capacitor,
two copper plates,
and several...
1. Determine the equilibrium temperature distribution for a one-dimensional rod composed of two different materials in perfect thermal contact at x=1. For 0<x<1, there is one material (c\rho=1, K=1) with a constant source (Q=0), whereas for the other 1<x<2 there are no sources (Q=0, c\rho=2...
Hello,
I'm puzzling over the likelihood of building a dry-running air motor for 25khrs @5-20kRPM.
I'm considering whether a small gear pump arrangement would doe the job - it only needs to output 6 shaft watts, but I'm concerned about wear.
Standard gears are avalable in steel and...
I've heard a lot of good things about the field of materials science, and the work being done seems really cool to me. But I'm wondering what a working materials scientist actually does. Does it use a lot of math and physics? Is it mostly lab work? Is it more qualitative? The reason I ask...
Homework Statement
The bars in the truss each have a cross sectional area of 1.2in^2. If the maximum axial stress in any bar is not to exceed 25ksi, determine the maximum magnitude of P of the loads that can be applied to the truss. Determine the elongation of each member.
E=29,000 ksi...
Dear Kind and Knowledgeable Contributors,
I am a graduate student in my first year debating between completing the rest of my PhD. program in Chemical Engineering or Materials Science and Engineering. My university allows me to switch into either field.
I believe I am equally capable in...
Homework Statement
A circular shaft AB has a torque T acting at the middle of the shaft, defined as plane C. Shaft end A is fixed while shaft end B is free to rotate (mounted in a thrust bearing). Finding the twist angle from A to C is not difficult, but the question requires that the twist...
Homework Statement
A plastic gutter is designed to catch water at the edge of a roof.
Manufacturers need to minimise the amount of material used to make their product. What is the best cross-section for a gutter? In this case, a circle.
Homework Equations
None, asside from...
Is specialization in radiation shielding and reactor/reactant materials a valid area of specialization? I am just worried if the two areas are too broad or different to name as my area of specialization. I ask this because I am trying to answer my applications for area of specialization and I...
http://spectrum.ieee.org/nanoclast/semiconductors/nanotechnology/nanostructured-metamaterial-enables-invisibility-cloak?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+IeeeSpectrum+%28IEEE+Spectrum%29
"We can even have amplification of light instead of its absorption. Here, for the...
Hi,
I am not a physicist. I am trying to understand something about the behaviour of materials for computer graphics applications.
I am trying to get an intuitive understanding of refraction. As far as I understand it - and please correct me if I am wrong - lightwave's phase velocity is...
I have a number of materials all mixed together in a beaker, my task is to extract each material individually, and get the weight of those materials.
The materials in the beaker are:
-Olive Oil
-Copper 'bits' about the size of rice grains
-Beach Sand
-Iron Filings
-Gravel - pebbles...
i understand that light 'slows down' in a refractive material when passing through it, but is this an actual drop in speed, or is the light absorbed and re-emmiited etc, so that its actual velocity does not decrease, merely the appearence of it. does time slow down inside optical material?
Hello,
I am currently getting ready to start applying Ph. D. programs, but I am unsure whether I want to continue with physics or materials science (I will graduate with degrees in both physics and materials science). I am wondering whether career options will be better for a physicist or...
Could some one explain, or give me a pointer to a good explanation, of how the nine constants that are often used to define orthotropic materials are determined.
I understand what E is in each direction.
I understand poisson ratio.
I sort of understand G. (I understand it as the E...
I have found plenty of study materials, notes and links on Classical Mechanics and Quantum Mechanics. However I could not found any forum on this site that provides study materials of solid state physics. So please if you have got the link, please post it in here.
Is the only way to find a material's or compound's behavior at the nano scale through experiment or can we deduce its characteristics through some other way or theories?
I am a solid state physicist. I feel bad that I know nothing about global warming (in terms of the details: what experiments have been done, what models exist, key papers, what, if any, real controversy there is).
What resources would be recommended? What papers, books, websites? It is...
I am about to talk to a prototype company and need some advice on O ring, friction and seals.
I am creating a device that works on slight water pressure differential. I have a piston like structure that is cylindrical and there will be an o ring inside the cylinder. The gas/liquid that the o...
Remember those executive toys that were popular in the '80s? You have a steel ball on the end of a thin rod hitting another steel ball that is stationary. As near as we can see, the target ball gets all the momentum of the moving ball, and the moving ball stops dead - close to 100% transfer. But...
Hi everybody,
I have this simple question. ¿Where can I find the covariant maxwell equations in materials?. I've already one and proved they correctly represent the non-homogene maxwell equations, is this one
\partial_{\nu}F^{\nu\mu}+\Pi^{\mu\nu}A_{\nu}=J^{\mu}_{libre}
with the tensor...
Hello folks! I have a few questions regarding plastics. I am pretty new to material science, so please bear with me...
I am actually looking for a material with a set of specific properties that my design requires: good impact resistance, moderate to high thermal resistance / high melting...
Homework Statement
A shaft fixed on both ends is shown below. It is made of a steel tube, which is bonded to a brass core. A torque T_D is applied at location shown. The tube is fixed at both ends.
[PLAIN]http://img202.imageshack.us/img202/2940/problem2eb.jpg
Show that the fraction of...
Homework Statement
The magnesium allow tube (AM1004-T61) AB is capped with a rigid plate. The gap between E and end C of 6061-T6 alluminum alloy solid circular rod CD is d[m] when the temperature is T_1 degrees celcius.
[PLAIN]http://img27.imageshack.us/img27/8867/problemwn.jpg
The...
Homework Statement
1) Why, in general, do brittle materials not achieve their theoretical tensile strengths?
2) Why, in general, do ductile materials not achieve their theoretical shear strengths?
Homework Equations
None needed. Wordy answer.
The Attempt at a Solution...
Homework Statement
A propeller shaft in the largest and most powerful ships transmits about 50,000 hp. Assume that the propeller transforms this power into a forward push on the ship with an efficiency of 70 per cent and that the ship's speed then is 30 knots (1 knot is 6,080 ft/hr).
The...
I´m trying to find approx. numbers or formulas for a submarine like structure to mantain a constant volume. For a given volume, which materials and to what thickness should the container be?
I apologize if these questions have already been answered, but I couldn't find quite what I was looking for by searching.
I am a junior in high school trying to get an idea of what I want to major in. I like (and am good at) math, physics, and chemistry, having taking the AP classes for these...
Hey,
Just wondering how to explain the yield point run-off for low carbon steel. Why does LCS have an upper yield point, followed directly by a lower yield point?
Thanks,
-Spoon
Hello. I'm interested intaking a cloud formed of activated carbon particles and particulates of some other substance to produce static electricity similar to that formed in a cumulonimbus cloud. The means of containing this experiment is another matter. I understand that when "opposite...
I wonder if there is any theoretical knowledge how to predict which atoms will decay first in given radioactive substance? I was asking about this in school and teacher said it is not possible to predict this...i doubt this process is random...
Thanks
Hello everybody!
I have an question, that seems silly, but i really need know that.
When a material is subject to waves, he starts to oscillate in the frequency of the wave and this material becomes a source of secondary waves, this justifies including the reflection process of the waves...
Hello Everyone
I have a mechanics of materials questions which I have been stuck on for hours, I just can't figure it out.
Attached is the questions.
I know the formula for deflection which is PL/ AE
but what do i do with that formula in this situation?
Any help would be...
Can anyone help me understand why magnetic flux flows through ferromagnetic materials like an iron ring?
Also, say you have a toroid with a wire wrapped around it (in air) how can you say that the flux that goes through one "loop" will go through ALL the others?
These are just some things...
Is it correct to say that all materials exhibit some form of magnetism?
I was reading on Wikipedia that there are different kinds of magnetism (Ferromagnetic, ferrimagnetic, Paramagnetic, Diamagnetic) and that all materials exhibit at least one of them.
A cable has an unstretched length of 12.0m and is stretched by 1.2 x 10^(-4)m when a 6.4 x 10^(8) Pa stress is applied. What is the strain per unit volume in the cable in J m^(-3), when this stress is applied?
Any help would be very nice. I don't understand what to do.
"interactions between polar materials and electric field"
sorry typing error.polar materials are those who have a permanent dipole ( like water molecules ) but these dipoles doesn't appear on the macroscopic scale due to their random orientation , so what if this polar medium is subjected to...
Homework Statement
Calculate the fraction of lattice sites that are Schottky defects for cesium chloride at its melting temperature (645C). Assume an energy for defect formation of 1.86eV.
Homework Equations
Number of lattice sites per cubic meter (N)
N=(NA\rho)/(ACS + ACL)
Where...