Constants Definition and 458 Threads

hi everybody...:cool: I'm looking for materials with dielectric constant 10,94 and 32,8... Please help me.. if you want to respect me, please send email to: alexz_lib3rty@yahoo.com Thanx...Gbu all

Sorry i ditched the template but as this is an experimental question i wasnt sure that it was needed. FOr Physics i am currently writing up an experiment which i had to do i class, the experiment was based upon finding te spring constants of springs by hanging masses on them and measuring the...

Hi Is there anywhere a list of all constants (with their values) and fundamental equations (which can not be constructed from any other equations) of the standard model? thx einKI

Homework Statement Problem: http://img147.imageshack.us/img147/8509/physjc9.gif Additional info: mass of the lander 7750 kg, 1.790967742 is the mag of acceleration due to gravity, this info was found in earlier parts of the problem Homework Equations I used these 2 equations and...

I'm trying to calculate some simple constants to high precision -- a few tens of millions of decimal places, maybe even a few hundred million. Are there any good programs out there that are fast at doing this? I'm using PARI/GP right now, but it's taking quadratic time to calculate ln(2)...

Homework Statement Solid cylindrical copper rod 0.2m long has one end maintained at temperature 20K, other end blackened and exposed to thermal radiation from surrounding walls at 500K. As the rod is insulated, no energy is lost or gained except at the ends of the rod. When equilibrium is...

Does anyone have a link or know a website where there is a table of values of lattice constants for NaCl, LiF etc? I'm asking because I was supposed to be provided with a table of values for writing my lab report, but unfortunately the lecturer seemed to have got 'array'. Any help and...

Hey, I have a normalized wave function PSI = c_1 psi_1(x) + c_2 psi_1(x) where c_1 and c_2 are constants with the eigenfunctions equal to ground and first excited state. The average energy of the system is pi^2hbar^2/(ma^2) - what can one deduce about the constant and how? Thanks...

http://img178.imageshack.us/img178/75/43802nv4.jpg A child's pogo stick (see figure) stores energy in a spring of spring constant k = 40000 N/m. At position A, x1 = -0.150 m, the spring compression is a maximum and the child is momentarily at rest. At position B, the spring is relaxed and the...

I need a refresher on calculus need to derive this equation, the question is: A --> B --> C and where decay constants: http://img183.imageshack.us/img183/4403/aki2.jpg Derive an expression for the activity of B as a function of time. So what I'm having trouble with is changing the...

Hi all, I was just working on a problem involving gravitational constants like \frac{\Delta(g)}{g}. Anyway, its been awhile since I have been in my intro physics classes and forgot how to make approximations that allow the adding of large numbers with small numbers (in my case 9.80665 +...

why should there is a 'constant' in a formula in which charactors on both sides are propotional to each other? and what should be the importance of it?:confused:

Hello, I want help in the line integration of: Integral( 1 dy + 3 dx ), over the curve C. Where C is the union of two line segments: Line 1 from point (0,0) to (1, -3) Line 2 from point (1, -3) to (2,0) The thing is I do not know what to do with the integrand being composed of...

The following matrices are written in Matlab codes form. The standard basis for so(3) is: L1 = [0 0 0; 0 0 -1; 0 1 0], L2 = [0 0 1; 0 0 0; -1 0 0], L3 = [0 -1 0; 1 0 0; 0 0 0]. Since [L1, L2] = L3, the structure constants of this Lie algebra are C(12, 1) = C(12, 2) = 0, C(12, 3) = 1...

Today someone has asked me about the evidences about the variations of fundamental constants (mainly alpha) As it is known that variation attemps versus the equivalence principle. So i wonder, if that variation would be irrefutably confirmed how would it affect LQG? I mean, LQG...

Hi, Could someone explain why when comparing a materials dielectric constant in solid form it is sometimes higher in pellet form and sometimes lower for other materials. For example, Polypropylene has a dk = 1.5 when in a solid (lump) block. This then becomes dk ~ 1.5 - 1.8 when in pellet...

I need a huge table of the dielectric consant and breakdown of various materials... I have looked all over the net but can only find small tables with 5-10 materials...

The Problem: A car is to be hoisted by elevator to the fourth floor of a parking garage, which is 48ft. above the ground. If the elevator can accelerate at 0.6 \frac{ft.}{s^2}, decelerate at 0.3 \frac{ft.}{s^2}, and reach a maximum speed of 8 \frac{ft.}{s}, determine the shortest time to make...

If 6.8 * 10-4 is ionisation constant(IC) of HF, what is the IC of its conjugate base. HF +H2O -----> H3O+ +F- So F- is the conjugate base(CB) I figured the IC of CB would be the reciprocal of IC of HF. But the answer given is the same but multiplied by Ionic product of water i.e. 10-14 Please...

a. If the equilibrium concentration of AB3 is 1.5600 mol/L, and the equilibrium concentration of B2 is 0.3300 mol/L, determine the equilibrium constant for this reaction. 2AB3 (g) <-> A2 (g) + 3B2 (g) Well, K_c = [B2]^3[A2]/[AB3]^2 [B2] = 0.3300 M [AB3] = 1.5600 M [A2] = ? [A2]...

Given a, b are constants and lim x approch 1, a root x+3 - b all over x-1 equals 1. Find a and b No clue how to answer this, but this is what I think i can do a) get rid of the sqrt b) apply limit See, the problem is I have to unknows so i don't know what to do

Im in calculus 1 and need some help Question: Find the vertical asymptotes for… F(x) = x^3 + 8 / x^2 –4 I got a va of –2 F(x) = 2x/ sin2x I got a va of 1 Find the limit Lim tan^2 2x/ x^2 x-0 I got 4 as my answer Lim x^2 –4 / (x + 2 )^2 x- (-2) I got –4/0 = no limit...

How is the permittivity of free space, \epsilon_0, and the magnetic permeability in vacuum, \mu_o, measured? Thanks

Before we differentiate, we must know whether a variable in that expression represents a constant or variable, correct? For example, if we have the function, f(x) = r^3 x^2 f'(x) = \frac{d}{{dx}}\left[ {r^3 x^2 } \right] (1) Now if r represents a variable then, f'(x) = r^3 \cdot...

What a tensor is .? I have found a text in my book that says that the electric and magnetic constants are tensors.. Do u have something in mind? Thx a lot

To determine the spring constant, k, in a static experiment (i.e. suspending weights from a spring) we use the following expression; k = (mass x gravity) / extension But what if I was on the Moon (where gravity is 1/6 that of Earth) or in part of space where there is zero gravity? The...

Hello, I have the following equation \int \!v{dv}=-{\it GM}\,\int \!{y}^{-2}{dy}\]} Integrating I get... \[\frac{1}{2}v ^{2}+C _{1}=-GM\essdot\left(-\frac{1}{y }+C _{2}\right)\]} Now how do I go from what I have above to this v ^{2}=2{\it GM} \left(\frac{1}{y }\right)+C \]} How it is...

I wanted to find the dielectric constant of different materials placed in a parallel plate capacitor using the equation: K = \frac{E_{dielectric}}{E_{original}} Where E = \frac{V}{d} I would use sensors connected to a computer to measure the voltage and i could easily measure the...

I am stumped... here is the problem: Solve the DE using the following: L and R are constants L\frac{di}{dt} + Ri = E(t) i(0) = i_0 E(t) = E_0*sin(wt) Here is my work so far: I got the integrating factor to become e^{Rt/L}. But now: \frac{d(e^{\frac{Rt}{L}}*i)}{dt} =...

this is just a general question, one that keeps coming up everytime i take a test or quiz. I understand that the derivative of a constant is zero, but I don't understand when you use that zero to multiply or divide in a problem, and when you just ignore that zero. For example x^2/3...

Find the Values of the constants in the following indentities. A(X^2 -1) + B(X - 1) + C = (3x -1)(x +1) AX^2 - A + Bx - B + C = 3x^2 + 3x -x -1 Ok, Is this correct so far? AX^2 = 3x^2 :. A = 3 Is correct ? Bx = 3x = b = 3 ? C = -1 ? I'm sure this is wrong, I just need...

It's not homework, but i think it can make someone think a little. \int\frac{dx}{x} Take it by parts. If you'll be as careless as me you can make a discovery :smile:

What would be the effect of an increase in temp on the rate constant of a) the forward reaction b) reverse reaction and my second Q is..why is it important to specify the temp when giving a value for Ke? Thanks

I was wondering if anyone knew of a database that contains Henry's Law Constants / solubility values for gases in relation to solvents other than water? I can't seem to come across any myself through google but maybe I'm just using the wrong search strings. In specific, I'm looking for K of...

2 Questions, pretty stumped on both. A meter stick is hung at its center from a thin wire (see part (a) of the figure below). Meter stick is hanging from a string, and being "rotated clockwise. It is twisted and oscillates with a period of 6.18 s. The meter stick is sawed off to a...

I'm taking my 3rd quarter on phys. in college right now (heat, sound, optics, & fluids this quarter), and I've noticed that neither here nor in high school was the knowledge of constants and formulae emphasized. Basically, you ask for a formula (as long as it's a simple relationship, not the...

the values of some of the fundamental numerical constants occurring in the standard models of matter and cosmology are considered to be favorable to life and people wonder why they are what they are for example the finestructure constant alpha, why is it around 1/137? for example the...

Hi, I am trying to determine the half lives of two radioisotopes in a neutron activated sample of copper. I have plotted the the ln(activity) vs. time and then used the linest function on excel to get a decay function for the longer half-life by assuming after a certain time, only the longer...

Do the physical laws make up the constants?

A(g) ----> 2B(g) + C(g) <---- When 1.00mol of A is placed in a 4.00L container at temp t, the conventration of C at equilibrium is 0.050mol/L. What is the equilibrium constant for the reaction at temperature t? Also have to Calculate the K(sp) for each of the salts whose solubility...

Hey guys, bit stuck here with this problem I have a differential equation for SHM here in the form x= A cos 10.7t + B sin 10.7t I need to find the constants of integration. w = 10.7 as above I don't have anything other than experimental data Time Second Distance / m 0...

Could anyone here say me what's the constants of van der waals for the Sulfur Hexaflouride (SF6)

Mark-Houwink-Sakurada constants - HELP! Hi! My local libraryes are closed theese days and I need the Mark-Houwink-Sakurada constants ("K" and "a") of poly(methyl metacrylate) in 1,2-dichloroethane urgently! :rolleyes: Does anybody know if i can find them online? where? Or does...

hallo guys. this is my first post( welcome me :-p !). Anyway I'm a freshman taking electrical engineering with a keen interest in physics. anyway my question is this: How do we know that physical constants are really constants. Ok, one way you might say is by assuming, that the...

Can anyone provide a good reference (preferably on-line), or a decent description, of how the fundamental constants of electromagnetism are experimentally determined? I'm talking about constants like the permitivity and permeability of free space. I'm also curious how the unit of charge...

The energy of a spring is the work done on the spring, and for a simple spring with F=-kx the energy may be changed by changing the constant k. In the non-linear case eg F = kx - 4qx^3 we would take the integral to obtain energy. But the question I thought was trivial was, "what values of k...

Hi, I just started a physical chemistry class and we are working on probability theory. The questions I am having a hard time with are as follow: we are given that E is proportional to exp[-E/RT]. It is stated that this is a simple system having only four energy states numbered 1 through 4...

Which of the following will prove not to be a fundamental constant?

What are the 26 constants of the universe? ie. i know gravity, electromagnetism, etc. but what are the values...? :confused: A link or some info would be helpful-thanks :approve:

I would like to hear comments from anyone concerning the below. Honest and critical feedback from qualified individuals is most welcome. Thanks for your reviews! This simple calculation bases the quantum effects of gravity on the electromagnetic frequency across ½ the Compton wavelength of...