Solid Definition and 1000 Threads

So, I was trying to find a rigorous mathematical derivation of gauss's law(please I don't want to hear again any field lines nonsense) and I stumbled upon jackson's proof which uses the solid angle concept and seems a solid enough proof(stupid joke:smile:).The problem is that it's the first time...

186000 miles long with zero flex or give. You have an observer at both ends. Observer A has a machine strong enough to turn the bar in either direction. Observer B does not know which way its going to turn. Mr.A turns on the machine and the bar turns to the left. Mr. B sees its direction...

Homework Statement Homework Equations The Attempt at a Solution What is the relation between a shell and a solid sphere? Can you give me some hints?

Homework Statement Been awhile since I've done them and my memory/reasoning isn't so great apparently... Use the triple integral to find the volume of the given solid: The solid enclosed by the cylinder x^{2} + y^{2} = 9 and the planes y + z = 16 and z = 1. 2. The attempt at a solution...

Find the volume of the solid that lies under the paraboloid z = x^2 + y^2, above xy plane, and inside the cylinder x^2 + y^2 = 2y First, i try to find the range.. i transfer it to cylindrical coordinates.. sqrt(y^2)=<z<=r^2 i don't know how to find r i know that phi is from 0 to 2pi...

Hello guys, I will soon be stepping into the IB1 program and before I start school in late august, I wish to properly* review my maths (including but not limited to algebra, geometry, functions, graphs, etc). * I really need to strengthen my mathematical foundation. I'm looking forward to...

Homework Statement A sphere is floating in water. It is pushed just under the water level and released. I'm asked to write the equation of motion for the sphere, not assuming small oscillations. Is it just: my''=\rho V g - mg ? Or do I have to include that the buoyant force is changing...

how close are the atoms in any solid, is all the space possible in a solid is filled up by its atom finally can we consider an atom an isolated body ,or can size of strings pass between inter atomic spaces.i believe atoms in the solid is not actually in contact but there exists infinitsimally...

Homework Statement The first quadrant area bounded by the curve x^3+y^3=8 is rotated around y-axis to give a solid of rotation. The question asks for an integral which represents the solid's moment of inertia around the axis. My answer is: I_y=M\frac{\int_0^2x^2ydx}{\int_0^2x^2dx}...

Hey. Thanks in advanced for the help. This site has helped me a lot through the years. Homework Statement Find the volume of the solid formed by rotating the area within y=e^x and y=sin x when 0<x<pi Homework Equations The Attempt at a Solution I've tried it like 10 times on...

I am working on a project and I am having a bit of difficulties with the math. It has been awhile since I took physics in college so please bear with me. I am attempting to calculate the amount of torque required to spin a solid cylinder resting upon a set of steel rollers. Attached to the...

Imagine a solid, non-conducting cylinder at rest in IRF K, with a positive spherical charge centered on one end and a negative spherical charge on the other end. Each charge experiences an electric force toward the other. The cylinder is compressed, but there is no torque. Let us say that the...

Hi guys, first of all I want to say that this forum saved me several and several times and I love it. I have a question for you related to absolute quantum yield of naphthalene determined with an integrating sphere. Do you have an idea how much should be? COuld you pass me a reference paper...

1.A solid cylinder rolling down a ramp without slipping. if the surface were slippery, would the time increase or dcrease. 2. PE+KE = PE +KE mgh = 1/2IW^2+1/2mv^2 F=ma f= mgsin(theta)/(1+mR^2/Icm) 3. Apperantly this question has several parts. The previous ones were related...

hello, Please attached snapshot of an answer to an Ex. I was stunned at the formula for the derivative of the solid angle which is : d(solid angle) = dvx * dvy I would appreciate if somebody can provide some hints on how one can find it ? Thank you,

How important is a solid (or better) understanding of Logic, especially Symbolic and Mathematical, for an aspiring mathematician? For a physicist? Other scientists? Are there variations in how important it is for Analysis, Topology and Algebra? A mathematically inclined physicist told me...

Look here: http://imageshack.us/photo/my-images/545/thep2.jpg/ I didn't learn about solid angle :shy: So.. I geuss sintheta Is h/r ? or sqrt(h^2-b^2/16)/r ? Am I right? Thanks in advanced

Homework Statement A 0.5m high and 100mm diameter post is to be made from concrete reinforced by 10mm diameter steel rods. How many steel rods should be used if the axial stiffness of the post is to be at least 2000kN/mm? Homework Equations n = number of steel rods D = diamater of the post d...

Homework Statement A solid circular steel drive shaft is 4 m long and 60 mm diameter. The modulus of rigidity of the steel is 85 GPa and its maximum allowable shear strength is 150 MPa. The shaft is used to transmit a power of 30 kW while rotating at 500 rev/min. Calculate the following...

Find the volume of the solid generated by revolving the region bounded by y = x2, y = 2-x2, and x = 0 about the y-axis. I'm taking Calc I and this question was on a test I took yesterday. A couple things about it didn't make much sense, which suggests to me that I'm missing something. I...

Preheating was carried out on a 4140, 2 inch dia. solid shaft material prior to welding of linkage plate and bearing was attached on the shaft. Temperature range is around 400 to 450 degree celsius. Welding was performed and followed by Post heating of temperature range 560 to 570 degree celsius...

I am less than a novice regarding electronic issues and understanding circuits , and need help in terms of seeking a component. I am looking for a solid state component---?? ic--- that would act as a SPST switch. This switching device would be inserted into a simple dc circuit--( approx 10-15...

Homework Statement The specific heat capacity per unit volume is denoted CV.Sketch Cv/T as a function of temperature T,in the limit T goes to zero, for both an ionic solid ,and a metal.Why do curves differ ? Homework Equations The question is very specific ,and in these cases as you know...

Homework Statement find volume of solid bounded by z=x, y=x, x+y=2 and z=0 The Attempt at a Solution first need to find domain. for x bounds, when y=0, x=0, when y = x, x+x=2 so x=1 therefore 0 < x < 1 for y bounds, x < y < 2-x now I am trying to work out what i integrate...

Homework Statement Find the center of mass of the solid of uniform density bounded by the graphs of the equations: Wedge: x^2+y^2=a^2. z=cy(c>0), y>=0, z>=0 Homework Equations Mx=int(y*p(x,y) dA) dA=area of integration, dydx/dxdy The Attempt at a Solution I set up all the...

Hello, I was following the derivation of the solid angle of right rectangular pyramid that I found at http://www.slac.stanford.edu/~bgerke/notes/solid_angle.pdf" . I don't quite understand the step between the 3rd to the 4th equation. In particular how the integral...

Hi All I have a question regarding what type of chemical/solution that is recommended to dissolve solidified Copper(I) chloride around a ceramic coated sample. I know HCl and ammonia both works well with the copper(I) chloride). However, I don't want to damage the sample. I have tried EDTA...

Homework Statement find volume of solid bounded by planes z=x, y=x, x+y=2, z=0 im struggling to visualise the solid. can anyone help me? I am not sure how so illustrate but any pointers would be appreciated! thank you!

Homework Statement A thin (1mg/cm^2) target of 48-Ca is bombarded with a 10-nA bean of alpha particles. A detector, subtending a solid angle of 2E-3 steradians, records 15 protons per second. If the angular distribution is isotropic, determine the total cross section, in mb, for the reaction...

Hello, Calculating the moment of inertia of a solid uniform sphere about it's center I get (3/5) Ma2. I know I am supposed to be getting (2/5) Ma2. I am using a differential volume dm as 4*pi*rho*r*r*dr, where rho is density, and r is the distance from the center to the differential volume...

I've already posted this question in the advanced physics forum, but I really think it should go here. My apologies for the double posting. Homework Statement If we are given a uniformly charged solid sphere with total charge Q and radius R, then the volume charge density rho is given by...

Homework Statement Find the volume of a solid between y = 0, y = x and x2 + z2 = 1 for all y >= 0. The Attempt at a Solution I'm having some trouble visualizing this, and what I'm not sure about is whether this is just a pyramid inside a cylinder (ie. straight lines from the base to the...

Homework Statement Find the volume of a solid whose base bounded by y=x+1 and y=x^2-1, with cross section of a square perpendicular to x-axis The Attempt at a Solution So i set up the problem like this delta volume= y^2*delta x, that being the area of the square where i get loss is...

Homework Statement The density of a solid sphere of radius R=10cm and mass M=15kg varies with distance from the center according to the equation p=po*e^(r/R). Determine the constant po. Homework Equations density= mass over volume. The Attempt at a Solution Change density to...

Just working on some practice problems. I missed a couple classes due to sickness and just need some extra help. If you could walk me through how to do these types of problems that would be amazing. Homework Statement Evaluate the volume of the solid bounded by the surfaces (x2 + y2)1/2 =...

Homework Statement Find the volume of the solid bounded by the planes x = 0, y = 0, z = 0, and x + y + z = 9. Homework Equations . . . ? The Attempt at a Solution After drawing out the picture with z=0 I have a line going from 0,9 to 9,0 bounded by the x and y-axis giving me a triangle...

Hi all, something strange has happened. I've had to speak with the universities I've applied to because a certain university demanded I respond to their offer of admission by March 09, and appeared to be reluctant to extend the deadline to March 18. (I later found out this was rather...

Homework Statement A light wave has a 678 nm wavelength in air. Its wavelength in a transparent solid is 493 nm. a) What is the speed of light in this solid? b) What is the light's frequency in the solid? Homework Equations v = λf The Attempt at a Solution a) I got the...

I'm have trouble with a homework problem having to do with find volume of an area. the problem reads: Find the volume of the solid obtained by rotating the region bounded by the given curves about the specified line. y=x^2 , y=0 , x=2 , x=4; about the line x=7 I've tried using the washer...

dear friends, i've noticed that the main feature of my inner experience is the sense that something exists, and that the main feature of my outer experience is the sense that something is solid, and I've wondered if these two experiences might be two views of the same thing: solid existence...

Homework Statement Consider a plane (hkl) in a fcc lattice, show the correspond miller indices (h1k1l1) in the primitive unit cell. Homework Equations The Attempt at a Solution so (hkl) intersect a/h,a/k,a/l in the fcc lattice right? but in the primitive unit cell of fcc, i...

Let's imagine that the interior of the Earth becomes completely solid. And suppose this happens within a period which is humanly observable (10 - 50 years?) I guess that Earth quake, volcano, continent drift will all stopped. Are there any other significant impact? Thanks in advance for...

When you have a cube made of any matter plastic, iron ,wood it is made of millions of atoms. But those atoms are held tight in the same shape. Why don't the atoms just fall away from each other and change into a very fine dust of molecules. What holds all these different elements together...

Homework Statement Find the area of the region bounded by y=0, x=9, y=x/3 and rotated about y=-2 The Attempt at a Solution The answer is \pi\int^{9}_{0}(2+x/3)-2^2dx I'm just wondering if this is the same thing as saying find the area of the region bounded by y=2 instead of y=0...

I was wondering - when pressure is applied to solids, do they heat up? Not pressure like an impact - I'm not talking about conversion of kinetic energy. But suppose a piece of iron is put in a hydraulic press and the pressure increases slowly. More specifically, I'm wondering about the rocks...

Alternatives to "Mesoscopic Electronics in Solid State Nanostructures" Greetings. I'm having a course called "Quantum Electronics", and one of the textbooks is "Mesoscopic Electronics in Solid State Nanostructures" by Thomas Heinzel. However, I find the book is often skipping an explanation...

Homework Statement Find the area of the surface generated when you rotate the parabola y=x2 0 less than or equal to x less than or equal to the square root of k, around the y-axis. You should end up with a simple formula in terms of the constant k. Homework Equations S=2\pi\intyds...

Hello! Does any of you know someone in Paris who is working on Solid State Physics using Quantum Field Theory formalism ? Thank you.

Title says it all really, I'm a second year undergraduate from oxford, and currently the textbook I've been using for stat. mech. is "Concepts in Thermal Physics", which was wirtten by my lecturer. I'd like (ideally) something a bit longer to work through suring the holidays, that would provide...

What does the ratio c/a mean in solid state physics? I have attached a table with a an example. Cheers