Solid Definition and 1000 Threads

I have been pondering in my mind that if mathematically a partial is made up of an uncountable infinity of space, then how do particles not dismantle and keep a solid a "solid"? This might be a confusing question so, sorry.

Hi I m studying modelling the viscoelastic passive properties of vascular walls and there is question! Why does Maxwell andKelvin-Voigt fail to represent a solid? and also what steps are required from a numerical point of implementation point of view , are required to turn an elastic model...

Hi all, I'm brushing up on some thermodynamics, and having been reading up on the interpretation of temperature as derived from kinetic theory. I can follow the derivation for an ideal, monatomic gas which relates temperature to the average, translational kinetic energy of the molecules. Most...

I was wondering if anyone could help me with this. I'm stuck and not sure where to start/how to go about it and finding the integral as well... Find the volume of the solid obtained by rotating the region bounded by the given curves about the specified axis. y=5x^2,x=1,y=0, about the x-axis

The problem is to find out the solid angle ω subtended by a disc of radius a at a point P distant z from its centre along its axis. α is the semi-vertical angle of the disc at the point P in question. The answer is supposed to be ω = 2π (1 - cos α), according to an online text. However, I find...

Is strain always recoverable in a viscoelastic solid? For instance, I thought in the single-branch Maxwell model, there was unrecoverable strain ... or am I wrong? And then if you use a two branch Maxwell model (one spring, one spring + dashpot), all strain must be recoverable, correct?

Dear PF Forum, I have no background in physics :frown: In http://math.ucr.edu/home/baez/end.html 1. If an Earth size object is left alone (assuming the Sun won't swallow it 2 billions year later). In 101500all of it atoms, oxygen (majority abundant in earth, right), silicon, nitrogen (abundant...

do each point in solid have a special energy state?

Homework Statement Find the mass of the solid bounded from above z = √(25 - x2-y2) and below from z = 4, if its density is δ = k(x^2 + y^2 + z^2)^(-1/2). Homework Equations m = ∫∫∫δdV The Attempt at a Solution The plane z = 4 is transformed into ρcosφ = 4, that is, ρ = 4secφ. And x^2 +...

In a solid, is electron's wavefunciton confined to a molecular orbital between atoms or is it delocalized and extends over the volume? According to valence bond theory, electrons are localized in bonds between atoms. But according to band theory (or Bloch wavefunctions), electrons are...

Homework Statement Use cylindrical coordinates to find the centroid of the solid. The solid that is bounded above by the sphere x2 + y2 + z2 = 2 and below by z = x2 + y2 Homework Equations x = rcos(theta) y= rsin(theta)[/B]The Attempt at a Solution I am having trouble trying to find the...

[Moderator's Note: Changed level of thread to "Advanced" based on the topics being asked about, all are graduate level topics.] I feel that I have an inadequate understanding of many important concepts in condensed matter physics, so I want to try to learn at least the most basic parts. So what...

Homework Statement the difference in length between an aluminium rod and a copper rof at 0 degreeC is 2cm. If they have the same difference in length at any temperature difference, what are the length of the 2 rods at 0 degreeC.? Al - expansivity = 20*10^-4 K^-1 Cu- expansivity= 15*10^-6 K^-1...

Hello,I'm new here and this is my first post. I am a freshman electronics and communication engineering student.I didn't study any quantum mechanics or solid state physics before(not in high school). But for my first year course i need to study solid state physics.The books we are suggested to...

Homework Statement http://prntscr.com/7rtrep http://prntscr.com/7rts95 Homework Equations theta = TL/GJ t(max)= Tc/J The Attempt at a Solution The two questions i have are rather similar so i put them up at the same time, i hope that's okay. For the first one ( the first link) i started by...

For a physics problem, I need to calculate the solid angle subtended by an oblique cone (cone where the apex does not lie on the line perpendicular to the cone's base from the center of the base). Consider the following problem: I have a 2D disk which emits light in an ever growing hemisphere...

As I understand it, the BB says the universe came from a tiny ball of stuff. Is it correct that no one has an explanation as to where the ball of stuff came from? Is it also correct that the BB is still speculation and subject to revision, even potentially discarding altogether?

Is there a solid that has a density of or below the density of air or any gas?

Homework Statement 1.The maximum energy (per unit volume) that can be absorbed by the steel alloy without sustaining permanent deformation is _______ lb/in^2 1.4. The maximum energy (per unit volume) that can be absorbed bythe steel prior to fracturing is _______ kip/in^2. . Homework...

Homework Statement Ok, don't get angry with me. The original problem is from Solid State Physics but my problem is very well in "Introductory physics". Here is the problem: The chain consists of molecules, which has three atoms, each with mass ##M##. Spring constant between the atoms inside...

I have to calculate the centre of mass of the drawn hemisphere. I don't understand where I make mistakes. The process I followed on the above image is the following: (I) Here I simply translated position vector components from cartesian to polar coordinates. (II) Formula of x-component of...

In the discussion of calculating specific heat for a solid, it is assumed that the whole solid body is a molecule with N atoms and the Hamiltonian of this solid is similar to that of a molecule with N atoms, i.e. ## \mathcal{H}_1=\mathcal{V}^{*}+\sum_{j=1}^{3n}...

In solid state physics, I learned that the velocity of a bloch electron is ##\frac{\partial E(k)}{\partial k}##, where ##E(k)## is the energy dispersion. This formula is derived on the basis of the assumption that electrons is a wave packet of bloch state in solids. However, I have a question...

Homework Statement I'm having trouble figuring out if a solid is a molecular solid or network covalent solid. Classify the following as a network covalent solid or a molecular solid: 1. CO2 2. SiO2 Homework Equations Molecular solid held together by intermolecular forces Covalent network...

Homework Statement A jeweler heats 25g of pure gold until molten. If the initial temperature of the gold is 22 degrees celcius, calculate the amount of energy required for the process. Homework Equations c = 129 Lf= 64 500 Lv = 1578000 Tmelt = 1064 The Attempt at a Solution Q = mct =...

In nuclear physics we have talked about the liquid drop model and the fermi gas model. My question is can a Fermi liquid and a Fermi gas be directly described using these models? Are they the same thing? i.e. If I wanted to decribe the difference between a fermi gas and a fermi liquid could I...

I have found via integration that the y coordinate is $$y =h/2 = 120 mm$$. The x coordinate is $$x = \frac{-4r}{3\pi} = -51.9mm$$ and the z coordinate is $$z = r - \frac{4r}{3\pi} = 69.1 mm$$. I have no answers in my textbook so can't confirm whether i am correct or not.

Homework Statement The problem is asking to find the change in temperature of forged cylinder. I know how to calculate this, , however I am struggling to find the work done on the cylinder, which is required to solve this problem. The cylinder is annealed copper, which is compressed from a...

Hello, In which way nano and solid state physics improve technology? where we use statistical physics more in nano physics or particle physics? where we use quantum mechanics more in nano physics or particle physics? which major is more enjoyable nano or particle physics? which major is more...

Homework Statement [/B] ZnS crystalizes in the B3 type structure with the space group is F¯43m. This structure is shown below and can be regarded as the bi-atomic form of the diamond lattice (F d¯3m). Upon applying a force along the [1,1,1] direction, the crystal might experience a change in...

To my understanding, QED is about electromagnetic interaction, and in a solid system, the interaction is only electromagnetic So why there are stills lots of research in solid state physics ? Is there something not explained by QED ?

we can use avogadro's law and gay lussacs law to find atomicity of gases but what about solid elements

Homework Statement This is a problem regarding transient heat conduction in an undefined semi-infinite solid, initially at a temperature T0 whose surface temperature is suddenly raised to a new constant level at Ts. I also supplied the problem as an attachment for ease in explaining the...

Hi all, I need help finding a formula to find the volume of a solid that has a fixed width and depth but 4 different heights. To see what I mean, please take a look at a sketch I drew below. Thanks.

Look at the diagram below, after all that doping, 2 blocks of Si have the same band structure? My understanding of band structure and fermi level is that: Given a block of solid (Please note, not a TYPE of solid, but this PARTICULAR block of solid) it will have its own unique band structure...

Hi all, I've got two questions about the emissions spectrum from solids. Question #1: I feel like I have a reasonable understanding of line absorption and emission spectrum of low density gases based on transitions of electrons between discrete allowed energy levels in a gas. I'm trying to...

Hi all, Having some trouble getting the final answer on the question below, the fact that the cube doesn't have a force in the x direction is throwing me off. Once I fine the force(??) in the x-direction, I can just use the generalized Hooke's law to obtain strain? Any help is appreciated...

Homework Statement Find the centre of mass of solid cone. Homework Equations $$y_{cm}=\frac{1}{M}\int_0^Hydm$$ The Attempt at a Solution First I took thin disks. I got the answer when I assumed its thickness to be dy but then dysecθ would be more accurate if half angle of cone is θ since...

Hi, thank you for your help in advance. I have a circuit configured as shown in this image. I got this arrangement from an earlier thread. An arduino controls a DC solid state relay, and it works fine when my load is a simple LED. The arduino is controlling through a digital output header and...

Homework Statement A point source emits visible light isotropically. Its luminous flux is 0.11 lumen. Find the flux whithin the cone that has half angle of 30 degree from the light source. Homework Equations luminous flux = luminous intensity * solid anlge The Attempt at a Solution I tried...

I'm trying to figure out how the element of solid angle transforms under a transformation between two inertial frames moving with velocity v w.r.t. each other under an arbitrary direction. But I should say I disappointed myself! Anyway, some books which contain a brief discussion on this(which...

Homework Statement A solid uniform hemisphere rests in equilibrium with its curved surface in contact with a rough inclined plane which is elavated by an angle α where sin(α) = 3/16. Find the angle between the symmetry axis of the hemisphere and the vertical.[/B]Homework Equations Sine rule...

Hey everyone! So I have that the low temperature limit of a paramagnet is Ω=(Ne/Ndown)Ndown while the low temperature limit of an einstein solid is Ω=(Ne/q)q. How could I explain that these two equations are essentially the same considering their respective limits (Ndown<<N and q<<N) and that...

Why is the solubility of some solids lower when the solution is heated? I read that it is because the process is exothermic (heat from breakdown is greater than the heat needed for breakdown). But why would having extra heat from outside sources inhibit the dissolving process, wouldn't it only...

Homework Statement I was looking for some practice problems in my textbook and found this problem that I was just a little stuck on. I drew the diagram from my textbook with the givens of the problem. Homework Equations ∲E*dA = Q (inside) / ɛ0 The Attempt at a Solution For r less...

Homework Statement My textbook says that the state of plane stress at a point is uniquely represented by two normal stress components and one shear stress component acting on an element that has a specific orientation at the point. Also, the complementary property of shear says that all four...

Hi there, I am new to electron theory, and have a question regarding fermi energy. The book I am reading plots the Fermi energy distribuiton function vs Energy for T=0 ( upper right graph in pcture) and for T not equal to zero. The book says that, when T does not equal zero, the decrease in the...

hello, i am looking for a book named "solid state physics: problems and solution" by mihaly and martin. 2nd edition. can anyone please help

Homework Statement Find the moment of inertia of a solid sphere of uniform mass density (like a billiard ball) about an axis through its center Homework Equations I = ∫rρdV The Attempt at a Solution I =ρ ∫r4πr2dr = ρ4π∫r4 Then I integrate this from 0 (the center) to R, so I = (ρ4π)*(R5/5) And...

Homework Statement https://fbcdn-sphotos-c-a.akamaihd.net/hphotos-ak-xpf1/v/t1.0-9/10980752_10204928958360361_5256945004598578166_n.jpg?oh=7fd9defb14be9a9befa0cf5032def429&oe=55576A2C&__gda__=1431534931_425423ae11039486a001b049726e1b11 Homework Equations Charles Kittel's book on Solid State...