Distribution Definition and 1000 Threads

Looking at another textbook problem, hope someone can let me know if I'm on the right track: Let $X_1, X_2, ... X_{25}$ be a random sample from some distribution and let $W = T(X_1, X_2, ... X_{25})$ be a statistic. Suppose the sampling distribution of W has a pdf given by $f(x) =...

What is the velocity distribution of evaporating H2O molecules? It can not be Maxwellian.

Homework Statement A sphere of radius R has a volume charge distribution ##\rho(r)## given by: ##\rho(r)= \rho_0 \left( \frac{r}{R_0} \right) \ \ for \ 0 <r<R## ##\rho(r)=0 \ \ elsewhere## Where ##\rho_0## is a constant. Use Gauss's law to find E field outside the sphere. Homework Equations...

Hey everyone, I'm hoping I can get some input on this. As some of you may recall, I'm currently in an internship at Fermilab, and I've hit a snag in plotting my data. I'm measuring the intensity of the NuMI neutrino beam at multiple different points to look for discrepancies in the measured...

Note: I have noted that one of the formulas I have provided does not show up on my webpage in preview mode and so have also made it as an attachment. Quick summary: I have found two different websites that offer the equation that I am looking for in different forms, but I am starting to think...

http://www.colorado.edu/physics/phys3320/phys3320_sp12/AJPPapers/AJP_E&MPapers_030612/Griffiths_ConductingNeedle.pdf I was reading this paper, and was confused by a result in section 2-A. (Heck they even mention they weren't expecting it themselves). The purpose of the paper is to find the...

hi i have MARSHAL-OLKIN exponential weibull distribution which have the following cdf and pdf.. how could i convert it to bivariate distribution? thanks

Hello, this is my first post and I've been out of school for a few years and now working a job in my field at a distribution utility, but I'm just really rusty or green on a lot of things now that I'm being challenged. Seems like the simplest questions elude me! Anywho, I've been tasked with...

I'm happy to find a forum such as this! I graduated college several years ago in electrical engineering, and last year finally landed a job in my field in distribution utilities! I like the challenge and using my degree, but I find myself having a lot of questions on how to do things. I don't...

Here is a question about probability density. I am trying to work it out using a different method from the method on the textbook. But I get a different answer unfortunately. Can anyone help me out? Question: Let X be uniformly distributed random variable in the internal [ 0, 1]. Find the...

derive f distribution as x1 and x2 are independent random variables having a chi-square distribution with n1 and n2 degrees of freedom.. aslo mgf and find raw moments ... and finds its mean and variance.?prove it ?help me guys?

I heard that the analysis of wave measurements close to shore verifies that as long as wave amplitudes are small with respect to mean depth a Rayleigh distribution remains satisfactory of wave heights, but how ?

If I pick up my Wife, who is in turn holding our Daughter, both me and my Wife feel the respective weights. Me of holding both, and my Wife of holding our Daughter. How is my Daughter's weight split between my Wife and I?

Hello My question could be about bars and litres/sec but I'll express it as volts and ampères, mathematically it's the same puzzle for me. How do you calculate the currents in circuits when there are devices whose resistances are not linear? In the following network there are 3 low value linear...

Homework Statement A gas consisting of 15,200 molecules, each of mass 2.00 x 10-26 kg, has the following distribution of speeds, which crudely mimics the Maxwell distribution: Number of Molecules - Speed (m/s) 1600 - 220 4100 - 440...

Homework Statement Given a semi-infinite stick (that is, one that goes off to infinity in one direction), determine how its density should depend on position so that it has the following property: If the stick is cut at an arbitrary location, the remaining semi-infinite piece will balance on a...

Homework Statement A common way of displaying the distribution of a random variable is by a histogram. Consider the interval [a,b) divided into M sub-intervals (bins) of length ΔX. Given a set of N random values of x, call Nj the number of values that fall within the jth interval. Homework...

Homework Statement Random variable x is defined on interval (1,3) and it has probability mass function f(x) =A(x2 +1= a) Find PMF, g(y) for y=x2 b)Expectation of y c)Variance of y d)Distribution function of y. e)most probable value of y The Attempt at a Solution As far as a), i integrated from...

Hi, Where can I find a database with the mass distribution and its movement in the well-known universe? Best wishes, Jens

Homework Statement the distribution function: f(x)= x + 1 when -1 < x ≤ 0 -x + 1 when 0 ≤ x < 1 0 otherwiseHomework Equations The Attempt at a Solution on the first interval i found (1/2)x2 +x + c on the second interval -(1/2)x2 + x + c and when integrating the c's will cancel each...

The expression relating the mean number of molecules with velocities in the range v and v + dv and position r and r + dr is given by where n = N/V is the number density of molecules. My question is: Since LHS is an integer, how do we ascertain the RHS is an integer, since it involves pi and an...

Homework Statement [/B] While shooting at target, soldier shoots from machine gun fixed in a way so it can rotate only around z axis. deviation from center of target due to twitching of machine gun is random variable with Gauss distribution. Deviations are such that inside of 20m from center of...

While linear accelerating an electron, with direction of acceleration being the ##z+## axis of the spherical coordinates, its radiation in angular distribution form is(according to this tutorial: http://farside.ph.utexas.edu/teaching/em/lectures/node132.html) ##\frac{dP(t')}{d\Omega} =...

Hi, I have read the static equivalent model of distribution system with high penetration of PV systems, using ZIP modelling technique. Now I want to create a dynamic equivalent model of distribution grid with high penetration of PV systems. How should I proceed?

Homework Statement demonstrate that the distribution factor is equal to 1 in concentric windings. Homework EquationsThe Attempt at a Solution i have tried to solve it doing the equations shown in this page, http://www.electrical4u.com/winding-factor-pitch-factor-distribution-factor/ but i...

good day all. Please can I see the maths calculation involved in obtaining the differential distribution frequency fm(D) in the attachment.many thanks

hello all.glad to be here! please in the attached document, column 5 and 6 which represents the differential and cumulative frequency distributions were obtained using equations (5) and (6). I'll be mighty grateful if anyone can give me a step by step breakdown of how it was done?? Many thanks...

I recently read that the charge density is less on surfaces with greater radius of curvature on the surface of a charged irregular conducting body . if anyone can provide a proof or explanation , please help!

Hi, I was trying to think of a way to generate a Poisson distribution using a single deck of 52. Say I am looking at the position of the Ace of spades in the deck after a number of shuffle rounds (1 shuffle round is 7 riffle type shuffles). Success is that an Ace of spades is on top of the...

Suppose the pdf is A*exp(-mv^2/2kT) , where A is the normalization constant. To obtain A I would integrate the pdf over the all possible values of v. The question is, should the limits be (-infinity,infinity) or [0,infinity) ? It seems that only by choosing the former can I get the correct...

Homework Statement The temperature distribution of a circ plate with radius ##a##, ##f(r,\theta,t)##, follows the diffusion equation ##\nabla^2f=\frac{1}{\alpha^2}\frac{\partial f}{\partial t}##, with a temperature of zero along the border. The initial temperature is...

Hi, so my question is along the lines of the following: If I'm looking at the decay channel H=>ZZ=>4 Muons, why would the resultant distribution for the mass of the parent Higgs be a Gaussian? Is it a case of the peak is the actual value of the Higgs at rest; those of greater mass are Higgs...

Hi Assume an x-coordinate from the unit circle is picked from a uniform distribution. This is the outcome of the random variable X with probability density function Xden(x) = 0.5 (-1 < x < 1). The random variable Y is related to the random variable X by Y = f(X) = √(1-X2) and X = g(Y) =...

Imagine an uncharged solid spherical conductor. Inside this spherical conductor, there is a cavity of a weird shape carved out of it. And somewhere inside this cavity, there is a charge +q (or rather, a charge distribution of total charge +q). The charge +q induces an opposite charge -q on the...

It's hard to type this out as there is a diagram and notation I can't find on the key board so I've attached an image of the question and answer. I've explained my solution below however I've also attached an image if it's too confusing with the lack of symbols! Problem involves uniform...

Homework Statement Due to the pollution from the industry around an apple farm, the apples grown there may be contaminated by heavy metals. It is believed that the amount of heavy metals in an apple of the farm follows the Normal distribution. N(16,16) which has a mean μ = 16 units and σ = √16...

I'm looking to model a system in which events are nearly perfectly randomly distributed but with a slight tendency for events to avoid each other. As you know, if the system were perfectly random, I could use a Poisson distribution. The probability distribution for the number of events would...

Homework Statement Automobile accidents occur in the United States over a 72 hour holiday period like events in a Poisson process with parameter lambda=10/hr. V is the time until the 10th accident a) what is expected value of V or E[V] and standard deviation? b) What is the probability that V...

in 11kv /230 v delta /star connected distribution transformer neutral not connected to earh,then if we touch the one phase (ex:R phase)of secondery line, shall we get shock or not?

Does anyone know the proof of joint moment generating functions for bivariate normal distributions? M_x,y (s,t)= E(e^(xs+yt))

Hi, so this is the example I have: Suppose that A, B, C are independent random variables, each being uniformly distributed over (0,1). (a) What is the joint cumulative distribution function of A, B, C? (b) What is the probability that all of the roots of the equation Ax^2 + Bx +C=0 are real...

While I do understand the story of the hypergeometric distribution, I was wondering if there's anything "geometric" about it, or if there's any connection between the distribution and "geometry". Can anyone throw some light on it? Thanks, Madhav

Hi all, The probability that a state is occupied means : 1) Fully Occupied by 2 electrons Spin up and Spin down or 2) Occupied by 1 electron only . Thanks

Dear all, I'm not a mathematician so please excuse me for a certain lack of strictness ... I work on random signals in physics, these signals are most of the time called "noise" for us. For example, we can speak about x(t), a time domain random signal. Very usually, the statistics...

In some books the radial distribution function is defined as 4pi*r^2*R(r)^2 and in others as r^2*R(r)^2. Thus, a factor of 4pi is differing. Which expression is correct and why?

i want to know the behavior of voltage in 11 KV underground and OH distribution line at different load conditions i.e. no load-full load ...

Homework Statement Four players play a board game which requires them to take it in turns to throw two fair dice. Each player throws the two dice once in each round. When a double is thrown the player moves forward six squares. Otherwise the player moves forward one square Homework Equations...

Hi, can anyone please guide me how to draw the distribution curves for radial wave function of an orbital? Please explain stepwise and in easy way. Thanks.

Homework Statement http://imgur.com/EiCFIDe Homework Equations E = kq/r2 λ = dq/dx Q = λa The Attempt at a Solution Here is the book solution: http://imgur.com/aKSeKo0 I need help with part (a). I understand everything in the solution except for the distance they used for between (r2 in...

It is a cylindrical ac machine. If we want to produce a sinusoidal voltage, we need B (magnetic density) to vary sinusoidally. To get B vary sinusoidally, we need to get H(magnetic intensity) to vary sinusoidally. To get H vary sinusoidal, the best way is to vary the numbers in the air gap...