Solid Definition and 1000 Threads

Hi, I am taking (ordinary) differential equations as a summer course and we are studying from a horrid textbook, in my opinion. Just curious if anyone might be able to suggest what is considered to be the "standard" introductory text on ODE. While I'm certainly interested in PDE, I don't...

Okay, so, we have y=2/x, y=0, x=1, x=3 and it's rotating around y=-1 As I understand it... This means (2/x +1)^2-(0+1)^2 (4/x^2 + 4/x) The integral of that is -4/x + 4ln(x) Am I right so far? Plug in the 3, and then the 1 -4/3 + 4ln(3) - -4+4ln(1) Then the result of that is multiplied...

Homework Statement A solid cylinder of radius R is spun and then placed on an incline having coefficient of friction μ=tanθ (θ is the angle of the incline). The solid cylinder continues to spin without falling for time: (A)Rωo/3gsinθ (B)Rωo/2gsinθ (C)Rωo/gsinθ (D)2Rωo/gsinθ The Attempt at a...

If it’s true that every atom has negatively charged electrons on its outer shells, and if it’s true that all matter is made of such electrons, be it our finger or a mountain or a planet, (meaning that all ‘things’ are negatively charged) and if it’s further true that what appears is not...

1.find tthe volume solid generated by revolving the region bounded y=sqrt x and the ;lines y=1, x=4 about the line y=1 2. using simpson rule witj n=4 to aproximate int from 0 to 1 1 over 1-x power 2 dx

Homework Statement The titleHomework Equations NahThe Attempt at a Solution It has no free moving ions or electrons Then, my teacher saw the electrons and gave 0 marks to the question(It was on the test paper) He said that if he didn't see electrons there, he would have given a mark. Why? I...

I was not sure exactly where to put this but it involves images so I thought it was no too inappropriate here. I was reading the Feynman Lectures Vol.1 and he says that Helium, although not solid at absolute zero normally, can be so in high pressures. I then googled this for images but none...

Homework Statement A small solid sphere of mass M0, of radius R0, and of uniform density ρ0 is placed in a large bowl containing water. It floats and the level of the water in the dish is L. Given the information below, determine the possible effects on the water level L, (R-Rises, F-Falls...

Hi, I am studying fluid mechanics and I am trying to get to grips with slip and no-slip boundaries. I know that: Slip ---> Occurs when fluid is inviscid so no viscous stress at boundary. No-slip ---> Viscous effects mean the the tangential velocity must be zero, relative to the boundary...

So, the igbt bridge system i have going is a 600 volt 300 amp full bridge of cm300 igbt's and i was wondering if a .660uf tank capacitor is too big for my system. The mmc is made out of 2000 volt 1uf capacitors, 2 strings of 3 in series. Thank you.

Hey guys, I would just like some confirmation that I got this question correct. Homework Statement For the stress block shown in Figure 3a, using the stress equations; a) Calculate the stresses sigmax' sigmay' and taux'y' on a stress block rotated 15° clockwise from the x-y axes...

Homework Statement Hey guys, I have a test coming up soon, and our lecturer gave us a sample test. I am working through it, but we have not been given any answers to confirm if what we are doing is correct. The Question: "For the simply supported beam (with upstand) shown in...

hello everyone, i am looking for a comprehensive link for the topic above as i want to do some research on various applications of x-rays in solid state physics. its a personal research but i have some materials but i still feel i need a whole lot more. Any form of help would be appreciated...

I am doing a project in Chemistry and I need to use Hess' Law to cancel two equations and if in one equation the NH4NO3 is solid and in the second one the NH4NO3 is aqueous. The equations are: 1: NH4NO3 (s) + HCl (aq) --> HNO3 (aq) + NH4Cl (aq) 2: NH4OH (s) + HNO3 (aq) --> H2O (l) + NH4NO3...

A solid has a circular base of radius 3. If every plane cross section perpendicular to the x-axis is an equilateral triangle, then it's volume is I keep on getting 18 root 3. But the answer is 36 root 3. Could I get some help? Thanks.

Homework Statement Use a double integral to find the volume of the indicated solid. Homework Equations The Attempt at a Solution I can't find what I did wrong, it seems like a simple problem... $$\int_0^2 \int_0^x (4-y^{2})dydx=\int_0^2 4x-\frac{x^{3}}{3}dx$$...

I bought a Stainless Steel soap bar and it works, it just does. It was from China and hollow inside and I would like to know if that's either a cost cutting measure or how the bar works? What would happen if it were solid? Another thing would be if it had a magnetic core, or made from a metal...

Homework Statement The figure shows a 200 g uniform rod pivoted at one end. The other end is attached to a horizontal spring. The spring is neither stretched nor compressed when the rod hangs straight down. What is the rod’s oscillation period? You can assume that the rod’s angle from vertical...

Homework Statement In Kittel's 'Introduction to solid state physics' (8th ed.), on page 167, it says "The wave functions at the Brillouin zone boundary ##k=\pi/a## are ##\sqrt{2} cos (\pi x/a)## and ##\sqrt{2} sin(\pi x/a)##, normalized over unit length of line." Here I cannot understand...

Homework Statement How to derive equation (22) on page 31 of Kittel's Intro to Solid State Physics 8th edition. The equation is: 2\vec{k}\cdot\vec{G}+G^2=0 Homework Equations The diffraction condition is given by \Delta\vec{k}=\vec{G} which from what I can surmise is the starting...

Homework Statement I'll provide picture for clearer understanding. The solid cylinder of mass ##m## and radius ##r## revolves about its geometric axis at an angular rate ##p## rad/s. Simultaneously, the bracket and shaft revolve about x-axis at the rate ##\omega## rad/s. Determine the angular...

Is it possible to create a solid whose sides are all quadrilaterals, and whose vertices are all bringing together four edges? I've been playing around in autocad and haven't been able to come up with a way to do this. I'm trying to make a checkerboard type of solid where no touching faces have...

Homework Statement 5. The nuclei of atoms in a certain crystalline solid have spin one. Each nucleus can be in anyone of three quantum states labeled by the quantum number m, where m = −1,0,1. This quant number measures the projection of the nuclear spin along a crystal axis of the solid. Due...

Homework Statement A horizontal 845.0 N merry-go-round with a radius of 4.3 m is started from rest by a constant horizontal force of 74.0 N applied tangentially to the merry-go-round. Find the kinetic energy of the merry-go-round after 2.2 s. Assume it is a solid cylinder. The...

I'm having some trouble with this problem: Find the volume of the solid of revolution, or state that it does not exist. The region bounded by f(x)= 6(4-x)^(-1/3) and the x-axis on the interval [0,4) is revolved avout the y-axis. How would I be able to tell whether to use the shell, disk, or...

Find the volume of the solid of revolution, or state that it does not exist. The region bounded by f(x)= the square root of ((x+3)/(x^3)) and the x-axis on the interval [1,infinity) is revolved around the x-axis. I tried using the disk method: pi* (sqrt(((x+3)/(x^3)))^2 Then I think I have to...

Homework Statement Silver has a density of 10.5E3 kg/m3 and a resistivity of 1.6E-8 Ω*m at room temperature. On the basis of the classical free electron gas model, and assuming that each silver atom contributes one electron to the electron gas, calculate the average time, Tau, between...

Why do atoms just have a general vicinity of which they rest in a solid?

Homework Statement Find the volume of the solid generated by rotating the region enclosed by y=\frac{1}{1+x^2} , x=-1,x=1 and y=0 about the line y=2 Homework Equations pi(outer radius)^2-pi(inner radius)^2 The Attempt at a Solution Since i am rotating around a horizontal line i figured...

hi guys! i was wondering if the solid magnet part of a brushed dc motor needs to be strong in order to make a strong motor? I'm designing a motor from scratch and wondering if i should use an existing ferrite magnet that is somewhat strong or should I design a electromagnet that is stronger...

hi,could some one please help me to understand how to find the density of water using a specific gravity bottle?and also a solid material..:cry: many thanks.

Homework Statement Find the volume of the solid generated by revolving the region bounded by the parabola y=x^2 and the line y=1 about the line y=1 Homework Equations V= integral of pi*r^2 from a to b with respect to variable "x" The Attempt at a Solution pi(integral of 1-(x^2-1)^2...

Supposing that some solid can exist at 2 different phases (had 2 different crystalline structure) at some temperature and pressure. Can we define the same reference entropy or chemical potential for these two states (knowing that we are talking about the same solid)?

what type of sold elements will not burn...even in the highest heat temperature..

Homework Statement Find the volume of the solid formed by revolving the region bounded by f(x) = 2-x^2 and g(x) = 1 about the line y = 1. Homework Equations V = ∏∫(1-f(x))^2dx - ∏∫(1-g(x))^2dx The Attempt at a Solution I keep ending up with ∏∫(1-(2-x^2))^2dx - ∏∫(1-1)^2dx, on...

Homework Statement The atomic mass of Niquel is 58.7 amu (atomic mass unit), and it's density (at 90ºC) is 8.86 g/cm³. (a) Find the distance from one atom to the closest one from him.Homework Equations 1 amu = 1.66053*19⁻²⁷ The Attempt at a Solution I started by finding the number of atoms...

Homework Statement Find the volume of the solid bounded above by the surface z = x^2 + y^2 and below by the triangular region in the xy-plane enclosed by the lines x = 0 , y = x , and x + y = 8. Homework Equations V = ∫∫ Height Base The Attempt at a Solution I first found...

Here is the question: I have posted a link there to this thread so the OP can view my work.

Homework Statement Find the volume of an object bounded by x2 + y2 ≤ 1, x2 + z2 ≤ 1 and y2 + z2 ≤ 1. Homework Equations The Attempt at a Solution This stuff is very new to me (multiple integrals to find volume) so I am not entirely familiar with it. My first thought was to put...

I have the following homework question I am working on. I am given three scattering angles: 42.8, 73.2, 89. (in degrees) without the wavelength of the light used. I am to show that these are consistent with a diamond lattice. I started with Laue's Law: delta(k) = G and according to the...

Homework Statement Question is attached in this post. Homework Equations Question is attached in this post. The Attempt at a Solution Disk Method with the radius equal to 1/(x^2+5x+6) ∫A/(x+2) + B/(x+2)^2 + C/(x+3) + D/(x+3)^2 from 0 to 3 I've used algebra to solve for...

Homework Statement A metal sphere with radius a is supported on an insulating stand at the center of a hollow, metal spherical shell with radius b. There is charge +Q on the inner sphere and charge -Q on the outer shell. Take the potential V to be zero at infinite separation. Calculate...

Homework Statement Find the volume of the solid of revolution obtained by rotating the area bounded by the curves about the line indicated. y=x2-2, y=0 about y=-1. Need only consider part above y=-1 Homework Equations V=∏a∫b[f(x)]2dx The Attempt at a Solution I'm mainly unsure of...

The way I understand plasma is that is almost a gas except some of the electrons of separated from the nuclei entirely making positively charged. Is there a temperature in which Iron is by definition a gas, and not a plasma? Also, can something like a noble gas become a solid?

Atoms in solid are more closedly packed as compared to liquid and gases. But we exert more force, some solid gets compressed but liquid doesn't, why? If atoms are loosely packed in liquid than solids, liquids should get compressed...

How I do for calculate the solid angle formed by 3 vectors like: http://s30.postimg.org/61lpvmi4h/solid.jpg ?

Here is the question: I have posted a link there to this thread so the OP can view my work.

A colleague and I want to model how a slab of PCM (wax) solidifies as it cools off. What I have noticed in my experiments is that temperature sensors on the top and bottom of the slab say it should be solid, as they read well below the melting point. But when I peek at the sample, the center...

Homework Statement The problem is attached in this post. Homework Equations The problem is attached in this post. The Attempt at a Solution I've set up the integral via disk method: π∫(e^√x)^2 dx from 0 to 1 I've done integration by parts by don't know how to integrate the...

Homework Statement NaCl (a0 = 5.64A° ), NaBr (a0 = 5.98A° ) and KCl (a0 = 6.30A° ) all have the same structure, which is the NaCl structure. (a) Assuming the spacings are determined by the ionic radii of the relevant ions, what would value would you expect for the lattice constant of...