Means Definition and 288 Threads

Homework Statement See the second bullet point on this page: http://facweb.northseattle.edu/rjenne/e240w13flr/hwflr/feb21/e240w13hwfeb21.pdf Homework Equations So I know that fft(x) for a bunch of sample points x={x1, x2, ..., xn} returns the n Fourier coefficients for a function...

Homework Statement Let X1,X2,...,Xn be i.i.d. Normal(μ,σ2) random variables, where the sample size n≥4. For 2≤k≤n-2, we define: Xbar = (1/n)SUM(Xi) from i=1 to n Xbark = (1/k)SUMXi) from i=1 to k Xbarn-k = (1/n-k-1)SUMXi from i=k+1 to n...

Hello all, Considering that Einstein told us that E=mc2, that means that any energy is generated at a cost of mass loss? to be more specific: When a power plant generates energy by burning gas or coal, a part of the particles in the fuel burned simply disappear and can't be found in the...

Homework Statement For simplicity, I'm leaving out extraneous details (like actual numbers). Also, apologies for my formatting; I don't know how to use Latex, but I tried to make this as readable as possible. I have a set of N measurements for τ which each have their own standard deviations...

Homework Statement A beam ABC is fastened in C and is supported by the axially loaded bar BD. There is a load F working in A. Disregard any friction. Use the given measurements to find the force in the axially loaded bar BD, the force in C and the angle of the force in C by means of...

Homework Statement A biologist interested in the mass of Chickadees (Poecile atricapillus) in North Glenmore Park collects the 3 samples shown below: Sample 1: 9 individuals with a mean mass of 13.23 grams Sample 2: 16 individuals with a mean mass of 9.64 grams Sample 3: 13 individuals...

Hello pf, Electrons are the charge carriers in metal conductor. while explaining about the fact the fact that electric field inside a conductor is zero, there is a depiction showing charge moves to surface (+ve and -ve charges to extremes of metal conductor surface) in emt books...

Homework Statement Prove that when speed is constant that V(T), and A(T) are perpendicular. Homework Equations I know this involves the dot product to show that the dot product of the vectors is zero. The Attempt at a Solution In my head I thought that since the speed is...

Can anyone explain proper time with a simple example analogous to real life please? I am having a problem understanding it. Thank you

Hey! I have this: 2(√(1-a^2 ))+ 2a How to determine the maximum value of this? I think good for this is Inequality of arithmetic and geometric means, but I don't know how use this, because I don't calculate with this yet. So, have you got any ideas? Poor Czech Numeriprimi... If you...

I'm a little confused as to what it is to be a college science professor. So if you get your PhD, your considered a scientist because you have done your own original research (at a university of course). Now you graduate and apply for jobs. I would assume that someone who is hired into, say...

I read this but don't know what it means Particles in a carbon atom interact with each other and their environment all the time, quantum field theory describes those interaction with creation and annihilation operators. I thought creation and annihilation operators created and destroyed...

I've memorized the following: pH<pka, then acidic form pH>pka, then basic form And I'm guessing that pH=pka means neutral. However, my instincts tell me it would be the opposite. Take NH3, ammonia, with a pKa of around 40. And then there's NH2-, which from a google search, has an...

I feel the question i am going to ask it is one of the most important question ,if not the most important,in Mathematics. And i may add if answered correctly a lot of misunderstanding and useless arguing can be avoided. So here is the question: What are the mathematical means or theories that...

Can someone please explain to me what moment of inertia means?? I googled it and I found that moment of inertia is an objects resistance to angular momentum? What does that mean exactly? Can someone please briefly explain to me (in English) what it means or give me an example? Because I really...

I was working out a conceptual question that asks: if a disk and a hoop of equal mass and radius start from the top of a ramp, are realeased at the same time, and roll without slipping, which one reaches the bottom of the ramp first? Disk: I = 1/2(m)(r^2) Hoop: I = mr^2 So the inertia...

Just started a Quantum Computing course, and I'm getting continuously confused and lost in the class. I don't think the class is "out of my league" as I've been able to ace every physics class I've taken so far, so I don't want to drop the class. That said, I'm getting confused at the most...

In W. Hoeffding's 1963 paper* he gives the well known inequality: P(\bar{x}-\mathrm{E}[x_i] \geq t) \leq \exp(-2t^2n) \ \ \ \ \ \ (1), where \bar{x} = \frac{1}{n}\sum_{i=1}^nx_i, x_i\in[0,1]. x_i's are independent. Following this theorem he gives a corollary for the difference of two...

http://www.google.com/patents/US685012?printsec=abstract#v=onepage&q&f=false Is this system used today in electrical transmission? If not why not?

Hello all, I got stuck with some problem of probability What I understand is how to verify by statistics, that a die (is that really the singular of dice ??) is crooked: - cast it a number of times, say twenty - count the number that shows most, say we find eight times the six -...

In alkenes, the more alkyl groups you're attached to means you are more energetically stable, and that we know the reactivity increases as the stability of the intermediate carbocation increases (with tertiary the most stable) I'm puzzled by this relationship, how is it that when it is more...

Dear all, Sorry to post this question in this section again. I am currently looking into few static analyse algorithms. I noticed that they are analysing with different order moments or cumulants to analyse the data. I guess it is because these algorithms are focus on different aspect of...

Let $a,b \in \mathbb{Z}$, and if $a+b\sqrt{2}$ has a square root in $\mathbb{Q}(\sqrt{2})$, then the square root is actually in $\mathbb{Z}[\sqrt{2}]$. Only one approach comes to my mind. Let $r_1, r_2 \in \mathbb{Q}$ such that $a+b\sqrt{2}=(r_1+r_2\sqrt{2})^2$. This gives $a=r_1^2+2r_2^2...

What does the unit "hp" means? I admit that my physics sucks because it has been a long time since I heard the word "physics" but putting that aside, what does the unit "hp" represent/means? I don't remember learning that unit in school. Eg. An engine develops 85hp I'm guessing it's a Power...

What does orbifold means? The wikipedia article says it is a generalization of manifolds which looks like a quotient space locally . So if my understanding is correct , If R1 is the Euclidean 1-space and A is an element of R1 and we identify each A with A+2*PI we get a circle so there is an...

As the title suggests, we know from the Abel-Rufini theorem that 5th order equations cannot be solved using radicals. I haven't managed however to find an either positive or negative answer to the following statement: "Can 5th order equations be analytically solved by means other than...

I've never read this explicitly, but here is what I've concluded: If you could somehow have a perfectly balanced load on the circuits in your home to each of the 2 hot lines coming into your residence from the pole mounted transformer, this would mean: The neutral wire connected from your...

I'm currently about to finish (next week!) my lower division physics classes and move on to the upper division courses while transferring from a junior college to UCLA. I feel utterly and completely unprepared for what lies ahead. I feel like the textbook we used (Fundamentals of Physics...

http://i.imgur.com/G36U3.jpg It's been posted in an obscure corner of the physics department forever and I think it'd be nice to know what the heck this is all about. Thanks!

I recall reading somewhere that the mean value of a continuous variable is situated at a point that acts as a fulcrum about which all other values are considered "weights". In other words, if we define the mean as μ = \int^{∞}_{-∞} x ρ(x) dx (where rho is the probability density) then...

It's a line through two half circles. Specifically: Imagine about 40% of the bottom of a circle above about 40% of the top of a circle with a little space between them and then a vertical line starting above the circles and going through the middle of each circle and then finishing a...

"unity" means just plain regular "1"? Im not sure whether this is a physics or math question, but in many physics problems, instead of saying "1", the problem will say "unity", like "the sine of theta is unity" or the "index of refraction is unity". I am assuming "unity" means just plain...

Just trying to check myself, as 14 bits doesn't seem to make sense...so I want to see how does it make sense. Is what written at the title true?

I was given an amplitude of a wave and was asked "What is the amplitude of each of the two counter-propagating waves that give rise to this standing wave" So since it says "counter-propagating" that means the waves are stacked on each other? so its really just half the given amplitude. Basically...

urgent reply needed Can we use partial means as a predictor for the response while fitting a regression line or curve?.

Constitution: Static or Living and in it means?? I was reading "The Original Constitution", by Robert G. Natelson. The work assesses Constitution and Bill of Rights in light of eighteenth-century law, minutes from the Confederation Congress, the original Articles of Confederation, Federalist...

Here is the scenario: Let's say that two sets of samples (SET 1 and SET 2) are from the same population (N=1000). SET 1 and SET 2 has the same sample size (n=500). SET 1 is composed of doctors only, and their average (mean) price that they are willing to pay for a certain product (a new drug) is...

I've be looking up research on Quantum Teleportation and after reading a discussion about it, it had me wondering. If it might be impossible, in some eyes, to have the information scanned from a human being and then send it to the desired location, would it be possible instead to step away from...

Hi, Recently I've started an experiment called Quantum Wells, I was reading the lab script and came across a familiar looking symbol but could not put my finger on to what it means. The symbol in question is: Å (an upper-case "A" with a hollow dot [circle] just above of it) Here's the...

what is research? how would you define it? what am I doing if I am researching? Ok, that's pretty vague. I am talking about academic research. I have been working in a so called Research & Development organization for past two years, and no doubt, I am loving it. I love the freedom, I love...

I have an example class yesterday, but one question troubled me. In part (b), why does E=nhf? For me, it seems E=nh is enough, why does the equation involve frequency f after quantization?

They say that nichrome is a better heating element as it has a higher resistance. But if I take V=RI then ain't I decrease since R is high, so current is lesser. Thus, resulting in a lower power dissipated as heat? Also, they aq if I use the wrong wires like thin wires, it will cause a lot of...

If I type in any equation for acceleration due to gravity, I can look and see that it will eventually become bigger than 186,000 miles per second. So, what's stopping the acceleration from being faster than light if the principal of the curvature of the fabric for space allows matter to follow a...

0 V is equivalent to short circuit. But applying 0V between 2 points means not connecting any source to those points (that is open circuit). Is not it? Please clear my doubt. -Devanand T

How much "bulge" means a bad cap? My 50" plasma first lost its component inputs a couple of months ago. I put in a up converting DVD player and more recently went to a Blue Ray on the HDMI inputs and all was good. But now the HDMI inputs have died also. I pulled the monster off the wall...

Sorry for such basic question, but am not able to get what it actually means? I know Hubbles "constant" is some 71 (km/s)/Mpc. Does acceleration of expansion means that the constant is getting larger? Or is it something completely different?

By spinning a magnetic field in the presence of conducting wire, how much voltage/current is produced? Thanks.

Homework Statement Suppose you have a collection of functions {f_1,f_2,\ldots,f_m} and you make the following statement: f_k ≤ 0 for all k with strict inequality for at least some k.Homework Equations The negation of the above statement is \exists k such that f_k>0 [\itex].The Attempt at...

Hallo alle users, as the title indicates, I have a question about measurement of thin film thickness by means of spectral reflectance. Given, the to be measured thin film has thickness less than 600 nm, but the measuring light has only wavelengh larger than 600 nm. Does it mean, that the...

Homework Statement Two people push in opposite directions on a block that sits atop a frictionless surface (The soles of their shoes are glued to the frictionless surface). If the block, originally at rest at point P, moves to the right without rotating and ends up at rest at point Q...