Material Definition and 1000 Threads

Homework Statement A laser is fired into a wet paper placed ontop of a glass plate of thickness ##d## and an angle of ##0## degrees. When the light hits the paper and goes through the plate it forms a circle of light of radius ##R##. What is the index of refraction of the glass plate? Homework...

Homework Statement I was told that yield point is a point which the material which will have an appreciable elongation of yielding without any increase in load . my question is If there's no increase load , how can the material elongate ? Homework EquationsThe Attempt at a Solution IMO ...

So I have been preparing to transfer into a physics program at the university from a community college. However, I am debating on whether I should go back and cover the material from my previous physics courses to build a strong foundation or if I should start learning the new material that will...

Hello! For an assignment I am planning to investigate the natural frequency modes of a circular membrane using the "Chladni technique". Usually, these Chladni plates are made out of metal, allowing them to be firm but still quite flexible. For my assignment I am planning on using a thin layer of...

How small would screen mesh have to be so that it would be consider waterproof? (ex: screen mesh small enough so that it would not break the surface tension of the water)

Hi Folks: This is my first post, I hope that I observing the proper etiquette. If I have a magnet with a known pull strength is there a way for me to determine the affect of 1/4 inch plywood on the magnets pull strength when the plywood is placed between the magnet and the surface metal? Thank...

Hey there, I'm struggling in finding the useful equations to determine some conformability parameters for a finite elastic material (EPDM) compressed on a rigid slightly wavy surface. I would like to optimize the thickness of the elastic material in terms of indentation depth and thus contact...

If I took a charged particle and accelerated it, that acceleration would have an effect on charges potentials, allowing for the radiation of electromagnetic waves. This acceleration would be local to a point in spacetime and the observed potentials would depend on the frame of reference of the...

Why is dielectric material used for anti-reflective coating? / Why not use a material this is NOT a dielectric material? Is it because dielectric materials are highly transparent?

I'm looking for a non-conductive material that can withstand pressures up to 35 MPa or about 5000 psi. It has to be in sheet form so I can layer on some electrical components I have. This may be a simple answer, but any help is appreciated.

We were learning about the change in free energy in class, but I was wondering since the Gibbs free energy decreases as a system becomes more stable, is the minimum absolute free energy for a material the same for every material, or can other materials be more stable than others?

So in glass, transparent liquids, and plastics is the eV for the electron known to science. The eV levels for electrons in gases are known like in hydrogen, and helium, but are they known for glass, and transparent liquids, and plastics. Or is it just too discernable to get. I am grateful for...

Hello, i am studying calculus and I am looking for a book or website that covers the following topics: -Real functions with vectorial variables (limits, domains, continuity, derivatives, directional derivatives, gradients) -Vectorial functions with vectorial variables (derivatives and...

... transmission of any electromagnetic radiation. I am trying to think of a way for em waves to pass through a solid opaque material, and then while the em waves are INSIDE the material, then some how the electrons absorb the em waves. Any em waves that get absorbed by electrons like light...

not a problem from anything just a question i have. problem: I know that youngs modulus (E) is known as stiffness. but when solving for elongation you can write e=FL/AE as F=se where s=AE/L and s is also known as stiffness. so I'm confused why is s and E known as stiffness when E is in the...

What is the difference between stiffness and Young Modulus and how can you calculate the stiffness?

Homework Statement gamma beam (γ) consequent of co 60 [this source have two beam; 1.1732mev(99.88%) & 1.3325mev(0.12%)] radiation behind the concrete block [ 300×300×20 cm] (thickness is 20 cm). analysis and plot Gamma-Ray Attenuation at 5 cm layers (4 layer) and plot spectrum of exited...

I'm only a uni student at the moment and this feels more like something you learn from experience than something taught in a lecture but I'll thought I should ask anyway. Is there an easy way to select materials for engineering projects? I was hoping to find there is a nice dictionary sized...

I would like to know what material would be the best choice for this set of requirements: - Non-conductive - Non-magnetic - Very low heat expansion (similar to iron/steel) - Readily available to work on (cut, glue, cnc) so I can buy in the shop in sheets or so - No need for melting or processing...

How are radiation sources like neutron or gamma/x-ray emitters used to detect materials? In particular illicit explosives and nuclear material and the such?

Is it true that quenching will decrease the toughness of material and tempering the quenched material will then increase the toughness? I need an explanation in term of the effect of quenching and tempering on the structure of the material.

Homework Statement The plates of a parallel plate capacitor of capacitance C0 are horizontal. Into the gap a slab of dielectric material with K=2 is placed, filling the bottom half of the gap between the plates. What is the resulting new capacitance? Homework Equations C = Q/V = κɛ0A/d The...

< Mentor Note -- thread moved to HH from the technical physics forums, so no HH Template is shown > Hi, I am having difficulty solving the problem, please resolve it if possible. my work and the image for the problem is attached. Thanks The 10 kg block is at rest on the bottom of the incline (θ...

Hi i would be glad if someone can help me on this. I am having a bit of trouble in understanding why the upper limit of integration over "r" is infinity in the MIT open course material on Electric field page #16 by Prof Markus Zahn (material attached as a link to the pdf). Please help. Thanks...

In material 38NiCrMov7-3 what is "3" Indicating. And anyone have properties of 38NiCrMov7-7 material.

Book says one of the properties of EM waves is they can impart momentum (and angular momentum)... What would be an example of this? (a simple example in terms of first year physics i mean)

Hi all, I hope you can help... I am by no means smart enough to calculate how thick the material needs to be for a project I am working on, usually I would go by trial end error, but I don't have the budget for that unfortunatley. I'm am trying to work out what steel thickness I would need for...

Hello all and thanks from advance, 1.I'm looking for a certain kind of material for a project of mine that can quickly absorb heat and in the same time quickly realesing (I guess that's the right term) heat. Of course it's all based on diffrent parameters, but I'm sure there is a better...

I'm working on making a little gadget for myself and am in need of a material that meets the following criteria: 1) non toxic 2) can double over on itself and return to it's original position* 3) rigid enough to avoid plastic deformation at maximum design deflection* 4) can be obtained in...

Hi there! Is there any ip65 rated enclosure material with electronic components inside but with no holes/cutouts that can act as a heat sink without overheating while the product is operating? Enclosure will need to be wall-mounted outdoors, it could be made out of die-cast aluminium which...

Hello, Am looking for special steel material ERCO, Which is use in spring manufacturing. Any one have idea about this. If anyone have then kindly let me know. I do not have datasheet or any physical or chemical properties.

Hey folks, My team currently uses mild steel aisi 1018 for their car chassis. While it is OK, we are looking for lighter alternatives. Problem is that we have to use mild steel ONLY. So I was wondering if any of you could give me a good alternative for 1018 that is lighter, has greater...

-iation. Could the opacity of a material to one band of EM radiation (light) could be altered by irradiating the material with another band of EM radiation (X rays)? I think you are suggesting that: By raising the electrons in the atoms to higher energy bands (with the X rays), so that they will...

Hi everybody, Not sure how to go about the question, so, will start by the narrowest scope... Basically, I am looking for a material with a melting point from 50 to 100C, cheap in volumes :), non-flammable, non-toxic and natural/recyclable. I was going for some kind of wax but flammability (?)...

Hello, I would like to do some experiment with superheated water on several hight temperature deegres (300, 450, 600, 750, 850, 900 °C). There is a problem and I need help. What kind of material could hold pressure of superheated water for a longer period of time (one week)? Please notice that...

-que to light?Someone said a atom is transparent to light to me. but as a material get more thicker, either in single atoms, or a micron, electrons start to absorb light, and there is no more transparency How thick does a material have to be before there is no more transparency. Like the...

In the past, reciprocating engine platforms have prevented the use of thermal insulating materials like ceramics due to, among other reasons, abrasion and vibration. One of the problems in the past has been the movement of the piston and piston rings over the cylinder wall where the insulating...

Homework Statement the tube has ID of 450mm, t= 6mm, OD= 462mm, pressure is 1.2MPa This is based on ASTM A36 steel, which have Ultimate Tensile strength 400-550MPa Yield Tensile strength 250Mpa Modululs of Elasticity 200Gpa Shear Modulus 79.3GPa Determine the factor of...

Firstly, it is a basic problem. I need to decide on a part of machine or anything for material selection presentation using CES Material Selector. I need a simple shape and simple property material because I can't calculate complicate dynamic loading so I need some limitations for instance...

Hi and thanks for reading. Is anyone aware of any material which can cool from 220°C, to a safe to touch temperature within a few seconds. I guess I am looking for something with a low ability to store heat. or very good at emitting heat. Possibly metal or ceramics. It would be heated to...

I am 15, didn't pay attention in school, because I thought it wasn't necessary, I am reviewing every mathematics concept I should know, but no clue which ones to start out with, anyone got a idea, and in which order I should relearn them in? (Just btw, I learn faster then others, I just wasn't...

Good evening, I'm an undergraduate astrophysics student currently doing research, and I wanted to get the opinion of some knowledgable chemists about a particular reaction my professor and I wish to emulate. Using a specific type of laser (Nd: YAG, for example), I'd like to mimic something...

Hi, To begin with, I am not a native English speaker and have very limited knowledge regarding magnetic fields and thus want to apologize in advance for probable use of incorrect terms. http:// In the picture above, M represents a magnet. S is a material that is not allowed to be affected by...

Is there any real-world material that is both reflective and transparent in 3D? A simple plane of glass is 3D and transparent, but reflective only in two 2D planes. I'm looking for something that is reflective in a large number of parallel 2D planes so that the reflection has depth. How...

I teach soil mechanics and I introduce to my students brittle and ductile materials. Failure of brittle materials is obvious for them but not for ductile materials. Do you know any ductile material that can be easily broken by traction? Unfortunately I do not have any tensile testing machine so...

I am doing a project that relates to welding acrylic. I got the bottle today, and I can't use it because its flammable and has chemicals known by the state of California to cause cancer (makes you wonder why the hell they would market this crap). Are there any clean, non-flammable, and...

And what is the difference between refractive index and absolute refractive index? Why do we use relate two absolute refractive index to find the refractive index of a particular material say we need to find refractive index of water with respect to ice.and why do we always put the higher value...

This system consists of a shaft that is connected to a motor that is rotating at 200rpm. The whole shaft consists of two gears. The input power of the system is 500W. Is there a way i can calculate how exactly i can find the best material for my gears that is able to withstand the input power...

Hi. I am re-engineering a 40+ year old carburettor design. The current throttle slide has stress raiser flaws and is the same material as the mixing chamber that it slide interfaces with. The prototype slides were printed in ABS for fitment trials. The functional trials used Acetal allowing for...

Hi All, I have been taking a class recently, and for some reason or another, professor has chosen not to return neither assigned papers nor exams , although some homeworks have been returned. I brought it up and got a non-responsive answer to the effect of "we cannot just do that". I have...