Properties Definition and 1000 Threads

can anyone please explain this property of silicon: An excellent oxide as the low-refractive-index cladding material. thanks

Over the past couple years, I have self-studied all of the basic mathematics (algebra, geometry, trigonometry, and calculus). When learning something new, my approach has always been to understand the underlying logic of why I was doing what I did. I have a bit of a proble, however. I never...

I am new in the field of science please can you help me. I would I appreciate it. I am not that knowledgeable.

Homework Statement A dissimilarity measure d(x, y) for two data points x and y typically satisfy the following three properties: 1. d(x, y) ≥ 0 and d(x, y) = 0 if and only if x = y 2. d(x, y) = d(y, x) 3. d(x,z) ≤ d(x, y) + d(y,z)The following method has been proposed for measuring the...

Homework Statement True/False: If true give a proof, if false give a counterexample. a) If A and B have the same eigenvector X, then A+B should also have the same eigenvector, X. b) if A has an eigenvalue of 2, and B has an eigenvalue of 5, then 7 is an eigenvalue of A+B...

Homework Statement Explain the difference in the following properties of dimethyl ether and ethanol: 1) Solubility in water 2) Rate of evaporation Homework Equations The Attempt at a Solution 1) Due to the oxygen being bonded to 2 carbon atoms none of the hydrogen atoms in the...

Did physicists ever try to put empirical constraints on the properties of the aether? I recall reading a popularization by Isaac Asimov in which he remarked that the aether would have had to have a very low density, and then to explain the high speed of light it would have had to have a...

Homework Statement Give a physicist's proof of the following statements regarding energy eigenfunctions: (a) We can always choose the energy eigenstates E(x) we work with to be purely real functions (unlike the physical wavefunction, which is necessarily complex). Note: This does not mean...

Could someone look over this and see if I have any mistakes? I'm trying to show that ∫ y' dx = ∫ dy through definitions. http://imgur.com/6zCHYo5 Thanks!

Homework Statement The problem states to find a unit vector that is orthogonal to \left\langle1, 1, -2\right\rangle, forms an angle of \frac{\pi}{4} with \left\langle1, 1, 1\right\rangle and has v1 > 0. Homework Equations cos\theta = \frac{\vec{u}\bullet\vec{v}}{|\vec{u}||\vec{v}|}...

I'm not entirely sure on the properties of limits, but this seems to work. Could someone look over this for me? http://imgur.com/6zCHYo5

I'm reading the second edition of John M. Lee's Introduction to Smooth Manifolds and he has a proposition that I'd like to understand better Let M, N, and P be smooth manifolds with or without boundary, let F:M→N and G:N→P be smooth maps and let p\inM Proposition: TpF : TpM → TF(p) is...

Homework Statement The Attempt at a Solution I am working a physics problem and want to make sure I'm not making a mistake in the math. Here is my math inquiry: Say you have (a*b)(c*d) where * indicates the dot product, and a,b,c, and d are all vectors. Can you say that (a*b)(c*d) =...

Hello, I am think of using chrome paint to create a uniquely shaped mirror. I was wondering if anyone has done studies to quantify how much light is reflected from different types of chrome and how much the light scatter. I realize chrome paint isn't the same as chrome, but I couldn't find...

Not sure if this is the right place to put this (sorry, first post here) Suppose I determine that the position angle (PA) of a galaxy, in one band - observed by SDSS - is -85.4 ± 8.9°, and is 84.7 ± 10.9° in another. Assuming - for now - that the errors have a Gaussian distribution, and that...

Homework Statement Could anyone help me with these two problems? The answer for the first one is 89.5%- 91.2% and the second one is 213 grams of glucose, but I didn't get those answers. 1. In making candy, a certain recipe calls for heating an aqueous sucrose solution to the "soft-ball"...

\frac{1}{998001} has some interesting properties. It will list out every 3 digit number except for 998. It has the form 0.001002003004... Here's a video on some more details if you're interested. 998001

Am i correct in thinking that in a simple ds^2 =dt^2 - a^{2}d\underline{x}^{2} metric that: g_{\mu\nu}=diag(1,-a^2,-a^2,-a^2) and g^{\mu\nu}=diag(1,-\frac{1}{a^2},-\frac{1}{a^2},-\frac{1}{a^2}) thx

Applications: garage door openers: 40.0 , standard cordless phones: 40.0 to 50.0 , baby monitors: 49.0 , FM radio stations: 88.0 to 108 , cell phones: 800 to 900 , Global Positioning System: 1227 to 1575 , microwave ovens: 2450 , wireless Internet technology: 2.4 to 2.6 . Which of the...

Hi, There are materials with almost any combination of properties. Turning to the combinations of chemical properties with others, such as mechanical, thermal and optical ones I can name a number of examples of materials (i.e. with mechanochemical, thermochemical and photochemical...

Hey everyone, In the process of wrapping my mind around the properties of metals for a realistic rpg combat system I'm working on, I made the following chart. Let me know what you think, if it's right (arrows pointing the right direction, covering the region, labeled correctly, etc), and if...

Homework Statement An amount of saturated steam at a pressure of 10 Bar, undergoes an isentropic (constant entropy) expansion. The final temperature is 30C. Find the final specific enthalpy and specific volume. Homework Equations Saturated Steam tables, Linear Interpolation methods? No...

Hello I have a mathematical problem that I could not solve. Could you please give me some hints how to solve it? Let f: [0,1] \rightarrow \mathbb{R} be a continuous and on (0,1) a differentiable function with following properties: a) f(0) = 0 b) there exists a M>0 with |f'(x)| \leq M...

Hello, simple question here! When a voltage is regulated down or up in a circuit by, let's say a DC/DC converter, does the corresponding current increase or decrease respectively so that the system remains consistent with the laws of conservation of energy? In other words, I want to know...

Hi everyone, Im looking for an autonomous first order ode that has the following properties. For dependent variable x: x(t=∞)=0 x(t=-∞)=0 and the function x(t) has one maximum. Any help would be great. Rgds...

A photon has an energy correleated with its frequency. Photons can interfere. Can the same be said for other bosons, like the Higgs?

How do we show that \frac{d}{dt}\left[\int\!y\,\mathrm{d} x\right] = y\,\frac{dx}{dt}

A heat transfer of 9.5 x 10^5 J is required to convert a block if ice at -15°C to water at 15°C. What is the mass of the block of ice? So do I have to use the equation; Q= mcΔT ? and Q= mL ? And if so how do I use it?

At a local county fair, you watch as blacksmith drops a 0.050-kg iron horseshoe into a bucket containing 25.0 kg of water. If the initial temperature of the horseshoe is 450°C, and the initial temperature of the water is 23°C, what is the equilibrium temperature of the system? Here is...

Homework Statement Assuming that all matrices, A, B, C, and D, are n x n and invertible, solve for D. C^{T}B^{-1}A^{2}BAC^{-1}DA^{-2}B^{T}C^{-2}=C^{T} Homework Equations C^{T}B^{-1}A^{2}BAC^{-1}DA^{-2}B^{T}C^{-2}=C^{T} The Attempt at a Solution I must have missed something in...

Say we have a particle, what are the most fundamental properties that distinguishes it from another kind of a particle. What is written in it's identity card? Spin, electric charge, rest mass, mean lifetime.. what else?

I am reading Protter's book on stochastic integration and differential equations. On a couple of occasions the author used some properties of characteristic functions I am not familiar with. I would appreciate if someone could point me in a right direction. 1. p22 T31 - We are working with...

Beforehand, please excuse my ignorance in this field, as I am only beginning to delve into its astounding depths. So, as I understand it, Photons are the force carrier particles (gauge bosons) for the electromagnetic interaction (electromagnetic force). This given, one could pretty much say...

When do macroscopic properties of matter come into picture? When we consider 2 atoms, 20 atoms, 200 atoms or 200000000000… atoms? I hope I have conveyed my meaning?

I have an equation (constraint) which I wish to solve explicitly in terms of gd (or more precisely a scaling factor of the vector gd) but I am unsure how to manipulate the equation σi(G) = |uiHgd|-1 Background: (please feel free to skips this. Much of this inforomation is I'm sure...

Homework Statement Thermal energy is transferred to a solid. Three properties of the solid are: 1. volume 2. mass 3. specific heat capacitiy Which of the above properties determine the rise in temperature of the solid? A) 1 and 2 B) 2 and 3 C) 2 only D) 3 only Homework Equations c = Q/mΔT...

Hello Everyone! Suppose $f(x)$ can be written as $f(x)=P_n(x)+R_n(x)$ where the first term on the RHS is the Taylor polynomial and the second term is the remainder. If the sum $\sum _{n=0} ^{\infty} = c_n x^n$ converges for $|x|<R$, does this mean I can freely write $f(x)=\sum _{n=0} ^{\infty}...

Homework Statement An electric generating plant boils water to produce high pressure steam. The steam spins a turbine that is connected to the generator. a) how many liters of water must be boiled to fill a 5.0 m^3 boiler with steam at 50 atm and 400 degrees Celsius. b) The steam has...

Homework Statement Let ej denote the jth unit column that contains a 1 in the jth position and zeros everywhere else. For a general matrix An×n, describe the following products. (a) Aej (c) eTiAej? Homework Equations Rows and Columns of a Product Suppose that A = [aij] is m × p and B =...

Hello, I am trying to prove/disprove the following claims: (1) There exists a sequence a_n of positive number so that the series Ʃ a_n converges whereas the series Ʃ (a_n)^2 diverges. I believe I managed to disprove that. Is it indeed false? (2) There exists a sequence of real...

Homework Statement If lim f(x) as x->5 = -1/2 and lim g(x) as x->5 = 4 find lim [f(x)-g(x)] as x->5 Homework Equations The Attempt at a Solution My question: Am I supposed to substitute f(x) by -1/2 and g(x) by 4 and have [-1/2 - 4]?

Suppose G is a group and g,h are elements of g. Does (g.h)n=gn.hn if we don't know what the groups operation is.

Can someone explain the following statement for me? The best you can, would really appreciate it. "A wave function or wavefunction is a probability amplitude in quantum mechanics describing the quantum state of a particle and how it behaves. " I am trying to learn/understand how something...

If we consider a number 9999999………. infinite times then no other number that can be represented bigger than that without plus or multiply operation. So we can be sure infinity is an odd number am I right

Hi, I'm specifically trying to compute (VΔYT)-1, where V is nxn and orthogonal, Δ is diagonal, and Y is nonsingular. In general we have (AB)-1 = B-1A-1 But how do we do this in general for many matrices? Is there a method, and as long as the matrix dimensions agreed, does the...

How alternating current was transmitted over a long distance? If it is direct current then I can imagine the constant current will flow over that long distance but how ac? Compare with ac, why dc decreases as it is transferred over long distances? Thank you.

hello, Let T be a open, connected and bounded subset of ℝ3 which has a smooth boundary bd(T). Consider the equation Δu = -λu with either the Dirichlet condition (u=0 in bd(T)) or Neumann (where δu/δn = 0 on bd(T)). Define: \left\langle g,h \right\rangle =\iiint_{T}{g(x)h^{*}(x)}dx...

Homework Statement Let's consider a distribution function f=f(t,x^i,E,p^i). Is it true that \mathop {\lim }\limits_{p \to\infty}p^{\alpha}f=0 \forall\alpha\in R ?Homework EquationsThe Attempt at a Solution I think so, not sure though. Thanks in advance!

if we place a very thin rod of length 'l' in front of a source of some radiation of amplitude = length of the rod (l) ,and perpendicular to its direction of propagation (assuming all the radiation to be polarized in one particular direction), :- |...

Hello everybody, For a group project, we are supposed to propose several designes for a plank bridge over a river. I've tried to find this material's (plank wood) strength properties, or a stress-strain diagram to no avail. Do you know where I can find it? Also, is it reasonable for a...