Solid Definition and 1000 Threads

For calculating I of a uniform solid sphere, why can't we use thin spherical shells? When I try to use spherical shells I get (3/5)MR^2. Every single derivation uses thin cylindrical shells and end up with the correct expression((2/5)MR^2) but they never explain why it is correct to use...

I'm an undergraduate looking for a good low level textbook to read this summer in order to learn what I can about Solid State Physics. I have 2 semesters of Chemistry and quantum mechanics. Any recommendations?

Homework Statement Question is: FInd the volume for area bound between y = x ^ (1/3) x = 4y About the x -axis I found the volumes from 0 to 8 using the washer method and then multiplied that by 2 since they intersect at y = 0, -2 and 2 x = 0, 8 and -8 Is that wrong? Cause my answer...

Homework Statement Find the mass of a solid of constant density that is bounded by the parabolic cylinder x=y2 and the planes x=z, z=0, and x=1. The Attempt at a Solution https://dl.dropbox.com/u/64325990/Photobook/Photo%202012-06-07%202%2033%2024%20PM.jpg I first drew some diagrams to...

A radiation source at some point through the collimator of a detector. Modeled as 100 spheres tracing out the image of a circle on a plane some distance above the original position of the source. What I want to do is collect all the spheres that go through the top of a cylinder and then...

Homework Statement Use the shell method to find the volume of the solid generated by revolving the shaded region about the indicated axes. Now, I don't know how to put the graph on here, but the equations are below. The shape revolves around the line y = 2 to produce the solid.Homework...

Homework Statement I have to find two methods used to measure the density of a solid material and one method to measure a liquids density Homework Equations n/a The Attempt at a Solution got one method for the solids and have written this but my teacher wants me to find the...

I was reading about electronic band structure in wiki and I didn't understand why the conduction bands are necessary for flowing current in a material. If all the atoms in a solid shares valence band and all its eletrons, then these electrons may travel through the solid. I didn't get why the...

I'm finding myself stuck again. This time it is more in the set up then the solving. Find the volume of the following solid of revolution. The region bounded by y=\frac{1}{x^2}, y=0, x=2, x=8, and revolved about the y-axis. I am trying to use the shell method to solve this, as it seems the...

I am looking for some suggestions for Condensed Matter and Solid State books. I currently have a one semester undergrad (soon to be two semesters) of Quantum Mechanics background. I am especially skewed toward something along the lines of Dover books, since they are cheap, and some of them are...

Homework Statement a elliptic paraboloid is x^2/a^2+y^2/b^2<=(h-z)/h, 0<=z<=h. Its apex occurs at the point (0,0,h). Suppose a>=b. Calculate the volume of that part of the paraboloid that lies above the disc x^2+y^2<=b^2.:confused: 2. The attempt at a solution We normally do the...

Hey guys and gals. Hoping someone can help out with a problem I am finding myself stuck on. The question goes as follows. Solids of revolution. Find the volume of the solid of revolution. The region bounded by \(y= \frac{ln(x)}{\sqrt(x)}\), y=0 and x=2, revolved about the x-axis. The problem...

Homework Statement A uniform solid sphere has radius R and mass M. It is initially at rest but is free to move, floating in space with nothing touching it. It suddenly receives an impulse J at a tangent to its surface. As a function of R, M and J, find formulae for: (a) the linear...

I you look at the phase diagram, CO2 is in liquid state at 5,11 atm and t= -56 C. But why does he convert directly to solid state at 1 atm? Again, if you go down from five to one atm, you should be in gaseous state ? Is it have something to do with temperature ? What happens with temperature...

Hi, I would be happy if you could solve and explain following problem: Imagine some solid long object (wooden plank for example) being just like that in vacuum, free, without being fixed to any point of space. Then, imagine only one forse pushing this object in a certain point of object...

Hi, I'm working on a homework for my solid state physics class and I'm having trouble with this question: Homework Statement "We have seen many cases in solid state physics in which you can apply the concept of uncertainty principle to estimate some quantity. Describe two examples of a...

Assume we have a solid state hamiltonian, which is ellectrons plus nuclei plus all possible interactions: H = T_{el} + V_{el-el} + T_{n} + V_{n-n} + V_{n-el} Is it wrong to write down a self-consistent system of Green functions for electrons and phonons? G_{el}=g + gSG_{el} G_{ph}=g +...

Homework Statement ...Bounded by graphs of equations: z=xy, z=0, y=x, x=1 I don't know what z=xy is. The rest of boundaries are clear. I assume that when y=1 and x=1, z=1. But, is this a z=1 plane? Check my figure attached. Thank you. Homework Equations The Attempt at a Solution

Solid State Physics Help Please! (Instrinsic->Extrinsic) Homework Statement 3 samples of silicon with donor densities of: 1st sample: 10^18 cm^-3 2nd sample: 10^16 cm^-3 3rd sample: 10^14 cm^-3 for each, find out at what temp the sample transitions from intrinsic to extrinsic behavior...

The base of a solid is the region bounded by the parabola x2 = 8y and the line y = 4 and each plane section perpendicular to the y-axis is an equilateral triangle. What is the volume of the solid?(Barron's Problem) so I solved for x since y must be used because the cross section is...

Homework Statement The solid is above the paraboloid z=x^2+y^2 and below the half-cone z=√(x^2+y^2)The Attempt at a Solution First off, I would like to apologize if this question has already been posted. I'm new to the forum. I drew the two solids. According to the picture I drew, it seems as...

Homework Statement Derive the moment of inertia of a solid, uniform density, disk rotating about a diameter using vertical rods. Diagram: http://i.imgur.com/TQIjz.png Only the radius of the circle and the inertia of a thin rod is given Homework Equations Inertia of thin vertical rod = m*r^2...

Homework Statement y=x^2+1 X in (0,1) Homework Equations formula needed integral (PI [f(x)]^2 DX in the F(x) just plug in the equation right? The Attempt at a Solution took anti deritive of the original problem and came out with PI[1/3x^3+X]^2 my answer is 5.58 am i on...

Hi guys. I'm trying to calculate the total distance a marble (I'm modeling it as non-deformable solid sphere) will travel along a flat cardboard surface (I'm also assuming the cardboard does not deform). The sphere will initially be propelled by a known external force, it can be assumed that...

Hi guys not sure if this belongs in the homework section, anyway here goes! I'm trying to calculate the total distance a marble (I'm modeling it as non-deformable solid sphere) will travel along a flat cardboard surface (I'm also assuming the cardboard does not deform). The sphere will...

Homework Statement A solid insulating cone has a uniform charge density of rho and a total charge of Q. The base of teh cone had a radius of R and a height of h. We wish to find the electric force on a point charge of q' at point A, located at the tip of the cone. (Hint: You may use the...

Homework Statement If 100 grams of glass (specific heat .2 cal/g*°C) at a temperature of 500 °C is added to 20 g of 0°C water, what is the final equilibrium temperature? Homework Equations Q= mcΔT The Attempt at a Solution I know that I have to set the two equation against...

Homework Statement 1. Use polar coordinates to find the volume of the given solid. 2. Inside the sphere x^2 + y^2 + z^2 = 16 and outside the cylinder x^2 + y^2 = 4. 2. The attempt at a solution My attempt as following: 2<=r<=4, and 0<=theta<=2pi So I do a double integral of...

Homework Statement the base of a solid is the triangular region bounded by the line x=0 (on the y-axis), the line y = 0 (the x-axis), and the line y = −2x + 2. Cross-sections perpendicular to the y-axis are squares. Find the volume of S. Homework Equations The Attempt at a Solution...

Just wondering - What factor decides whether a solid takes up a crystalline structure or an amorphous structure? And if it takes a crystalline structure , what decides if it will be cubic, tetragonal, hexagonal , trigonal, monoclinic or triclinic?

Good morning, I would like to ask you... Is it possible to make a liquid matter from a solid matter with a help of ultrasound? At first, what happens if the ultrasound travels through a solid matter (for example quartz)? What happens to a solid matter during a positive amplitude (compression)...

Okay, I am not sure if this is the right subforum, but here goes: An einstein solid is a solid composed of N quantum harmonic oscillators, which can store evenly spaced energy units q. Now suppose we have an einstein solid of N oscillators with q energy units, where q>>N. My book wants to...

Homework Statement Trying to solve this integral \int_0^T \frac{dT'}{T'}\frac{d}{dT'}U(T',V) where the temperature dependent part of U is \Sigma \frac{h\omega}{\exp(\beta\omega)-1} The Attempt at a Solution using x = hw/T I find that I need to integrate \frac{x^3...

Hi, I am doing a project for the math department and in it I would like to revolve this piecewise (3) function about the x axis. I have found programs like winplot which are pretty easy but it will only show the finished product. I am looking for something that I can either manipulate or it...

Homework Statement Here is the surface I need to parameterize. It is a solid of revolution. Homework Equations The Attempt at a Solution So since its a piecewise function, I can define it as follows (x-2)^2 + z^2 = 1, 1<x<2 z = -x+3, 2<x<3 z = x-3, 2<x<3 I know...

Homework Statement Find the volume of a solid created when the area between the function y=x^2+1 and the x-axis (for 0<x<2) is rotated about the line y=-2. Homework Equations Vs = ∏*r^2*h The Attempt at a Solution I can't seem to set this up correctly and am thrown by the inner radius...

Hi Everyone, I have a question about panel vs. solid rod structures. Assume a two cubes of equal dimension and weight. Cube 1 is made of panels, ie. a hollow cube. Cube 2 is made with solid rod Material is linear elastic Which would be stiffer? I think the panel...

Why do LEDs and other light emitting solid state devices have a definite lifespan?

Homework Statement A solid sphere of radius a rotates with angular velocity ω\hat{z} relative to an inertial frame K in which the sphere's center is at rest. In a frame K' located at the surface of the sphere, there is no electric field, and the magnetic field is a dipole field with M=M\hat{z}...

Homework Statement Find the volume of the first quadrant region bounded by x=y-y3, x=1 and y=1 that is revolved about the line x=1. The Attempt at a Solution dV=∏R2t where : t=dy R=1-(y-y3) =1-y+y3 so.. dV=∏(1-y+y3)2dy dV=∏(1-2y+y2+2y3-2y4+y6)dy V=∏∫ from 0 to 1 of...

find the volume of the solid generated by revolving the area bounded by the given curve about the indicated axis:y = 2x-x^2 and y = x; about the y-axis The attempt at a solution: so i assigned values for x and y, and the curve is a parabola that opens downward with a vertex of (1,1), i used...

Homework Statement Find the center of mass of the solid figure similar to a cone pointing upward with slope = 1 Note: the density varies with z^2 and the edge has a slope of 1. From symmetry we see that both Xc and Yc are equal to zero. Find the center of mass in the z direction as a function...

There are two sphere of same radius but one is solid and other is hollow. Both are heated to same temperature(greater than room temperature). which will cool at faster rate? I think both the spheres will cool at same rate since hollow sphere can't loose it's heat inside it (because internal...

Hello, Am working on a model that involves heat conduction in a semi-infinite solid. I have been using linspace() command for finite geometry, but now i need to create a 1-dimensional semi-infinite solid. Any suggestions? Thank you.

Homework Statement A solid cylinder is pivoted about a frictionless axle as shown. A rope wrapped around the outer radius of 2 m exerts a downward force of 3N. A rope wrapped around the inner radius of 0.7 m exerts a force of 8 N to the right. The moment of inertia of the cylinder is 8 kg m^2...

Homework Statement Find surface area of solid of revolution obtained by rotating the curve: y=x2/40-5lnx from x=5 to x=7, rotated about x=-4 The Attempt at a Solution The problem is I know how to do this if I rotated it about x-axis/y-axis, but I have no idea how to do it if the...

What is "kinetic capacitance" in superconductors or in solid state in general? Hi, I would appreciate it if anyone could explain to me what "kinetic capacitance" is, particularly in the context of superconductors or solids. I understand "kinetic inductance" which comes from the kinetic...

Is there a general level of vibration that describes most solid state matter that we can touch? Perhaps in hertz?

Hi So the reaction is below: Sodium thiosulfate + HCl = Sulfur + NaCl+ Water+ SO2 So if I wanted to say 'Increasing the conc. of Sodium thiosulfate has shifted the equilibrium to the left (reactants) and thus the system works to break down excess reactants and create more product by...

Homework Statement In the picture belowHomework Equations Stress=P/AThe Attempt at a Solution I equated stress AB=-stress BC p/pi=-(p-60 kips)/2.25pi P=18.4615kips This is not the right answer according to the book