Example Definition and 879 Threads

What are two simple objects that can be modeled as particles? This has me totally stumped...

I think that the speed limit should be strictly enforced. It is horrible that we try to teach teenagers to obey important rules such as no drinking, no smoking, no harassment, no violence, etc but then when they start driving they are bombarded by examples of people blatantly breaking laws going...

Homework Statement Find the recurrence relation and the general term for the solution: y'' - xy' - y = 0 xo=1 Homework Equations y= sum (n=0 to infinity) an (x-1)^n The Attempt at a Solution i get: y= sum (n=0 to infinity) an x^n y'= sum (n=0 to infinity) (n+1)an+1...

can you example a function that is continuous at every point but not derivable

V(x) = \left\{\begin{array}{ll} 0, & \exists n\in\mathbb{Z},\; x\in [2nL, (2n+1)L]\\ \infty, &\exists n\in\mathbb{Z},\; x\in\; ](2n-1)L, 2nL[\\ \end{array}\right. This is a periodic potential. L is some constant. Is a solution \psi(x) = \chi_{[0,L]}(x)\;\sin\big(\frac{\pi x}{L}\big) of the...

Homework Statement I know this is a basic question but this is my first physics course ever and I am having big time trouble, any help is appreciated! Chipping from the rough, a golfer sends the ball over a 3.00 m high tree that is 14.0 m away. The ball lands at the same level from which...

I keep hearing about renormalization in quantum mechanics, frequently in the context of it's mathematical dubiousness. But no-one ever gives an example of this process. Could anyone give an example of a quantity that must be renormalised, along with some context? Even a very general one would do.

I'm not sure the double-slit experiment is one such example, maybe I have not understood it yet. This experiment shows the wave nature of light due to the wavefunctions of photons. But how does it show a particle of zero size that is not just a burst of waves?

Homework Statement Integral from 0 to 2*pi of [(Cos(3*theta)) / (5 - 4Cos(theta))] (d*theta) Homework Equations z=exp(i*theta), Cos(theta) = (z + z^(-1)) / 2, Cos(3*theta) = ((exp(3*i*theta)+exp(-3*i*theta)) / 2 = (z^(3) + z^(-3)) / 2, dz = (i*z) (d*theta) The Attempt...

Hi. I am learning special relativity and have decided to take Einstein's train example to practice some calculations. I have given the train speed v=1/4c and have decided on distances that make the side observer's space and time calculations straightforward. I have calculated everything using...

[SOLVED] Laplace transform, book example I'm having trouble following one of the steps in my textbook. They give a function: y(t) = e^{2t} and plug it into Y(s) = \int_{0}^{\infty} y(t) e^{-st} dt and compute. They end up with: \frac{1}{2-s} \underbrace{lim}_{b -> \infty} e^{(2-s)b}...

I'm battling with first order predicate logic (no identity, no extensions) and currently esp. inference using the so called "natural reasoning" rules for inference. Now, the textbook we use, is very ambiguously defined, even I have spotted several 'errors' in it, the lecturer even more. This...

[SOLVED] Griffiths Example 5.8 Homework Statement This question refers to Griffiths E and M book. In this Example, Griffiths says "the z-component of the B-field cannot possibly depend on the direction of the current in the xy plane. (Think about it!)" I thought about it and thought about...

Homework Statement I'm trying to come up with an example of a quartic polynomial over a field F which has a root in F, but whose splitting field isn't the same as its resolvent cubic. Homework Equations The Attempt at a Solution Well, I know the splitting field of the cubic...

Homework Statement Give an example of an operator whose matrix with respect to some basis contains only 0's on the diagonal, but the operator is invertible. The Attempt at a Solution I think the operator will not have an upper-triangular matrix since it would then not be invertible.

Homework Statement For each a\in\mathbb{R}, find a function f that is continuous at x=a but discontinuous at all other points. The Attempt at a Solution I guess I am not getting the question. I need to come up with a function, I was thinking of a piecewise defined one, half rational...

http://img211.imageshack.us/my.php?image=img86301qt1.jpg i have a trouble in understanding ROM i know that it has addresses and words and that its used in computers in order to store info. but when i get to the example i can't understand the functionality of it. in the example that i...

Homework Statement Suppose 30 identical juggling balls are distributed to 5 different jugglers. A) how many ways can the balls be distributed so that each juggler receives at least three balls? B)In how many ways can the balls be distributed so that each juggler receives between 3 and 7...

[SOLVED] Griffiths Example 3.6 Homework Statement Please stop reading unless you have Griffiths E and M book. In Example 3.6, we must assume that there is no charge inside the sphere even though it does not explicitly state that? Or is that what "hollow" means? Homework Equations...

[SOLVED] Griffiths Example 3.8 Homework Statement Please stop reading unless you have Griffiths E and M book. In Example 3.8, Griffiths makes two claims without justification that I want justification for. First, he says that V=0 in the equatorial plane (I assume this means that x-y plane)...

Hi, Anyone knows a good example to aply Poynting's Theorem? The one thas defines the conversation of energy in the electromagnetic field? Regards Martin

Homework Statement Prove that if a_n>or equal to 0, and sum(a_n) converges, then sum(a_n)^2 also converges. The Attempt at a Solution The only example I can think of is 1/(n^p) where p is any exponent greater than 1. Are there any other examples that I can use or do I only need to use...

I saw somewhere that the act of observing can affect whether light will show its wave nature or its particle nature ie whether the wavefunction will collapse. But then, it seems to me, it's not real observing as in the macroscopic world, we don't just observe, we absorb and therefore destroy...

Hi All, does anyone know how to solve the following first-order non-linear differential equation, a * y' + b * y^2 + c = 0 where a,b,c are scalar constant values. Thanks!

I have an example where a 5v dc source is connected to a 10mh inductor then to 1k and 2k resistors in parallel. In finding the current through the inductor at t=0: written is: IL(0) = 5v / (2/3k) = 7.5 ma what i got was: IL(0) = 5v / (3/2k) = 3.3 ma I'm just checking to make...

http://img214.imageshack.us/img214/3928/idontgetkm1.jpg For example 26, I don't see how (for the 1st part) n=9. In the definition of the summing of them it says n is the number above SIGMA, so why not 10? Is it to do with n=1, which isn't k=0 from the definition?

I'm looking some applied example of Laplace transform. For instance: If I have function f(t) = Asin(ωt + φ), where; A is peak deviation from center ω is Angular velocity t is time φ is phase and now I want to laplace transform it and get some function like...

Simple Robinson Crusoe (RC) economy. There are 2 periods. Price level p is given exogenously (e.g. through trade). RC is the "capitalist," he earns competitive profits (=0) so he is indifferent between producing and not producing. He doesn't have to eat to live. Friday is the laborer, he...

Could someone give and example of a substance that is a Bronsted-Lowry base, but not an Arrhenius base..

What is an example of a sound that is intense but not loud?

I'm aware of plenty of microbes that can cause multiple diseases if present in separate parts of the body: S. aureus causes disease just about everywhere it goes except the surface of the skin and nose, S. pyogenes causes strep throat in the respiratory tract and can be flesh eating if it gets...

How do you take the inverse of a matrix? The specific example I have is A= 1 1 1 1 1 1 1 3 1 1 3 3 1 3 3 3 Find A^-1

[SOLVED] Example on spherical coord. and trip. integral Homework Statement Here's the example in the book. They're proving the volume of a sphere using spherical coordinates. A solid ball T (the region) with constant density \delta is bounded by the spherical surface with equation \rho...

Define F(x) = integral (from x to 1) f take limF(x) as x goes to 0. I would like to give an example of a function on (0,1] so that the above limit exists but if we replace f with |f| the limit does not exist. So I came up with f= [(2^n)/(n)](-1)^(n+1) for x in (1/(2^n),1/[2^(n-1)]]...

Is there anybody here can give me a chemical engineering example that the final differential equation will be LAGUERRE ?

Homework Statement An 88 kg man drops from rest on a diving board 3.3m above the surface of the water and comes to rest 0.58 seconds after reaching the water. Acceleration due to gravity is 9.81 m/s^s What force does the water exert on the man? in N Homework Equations F = ma a...

Can anybody please give me an example of INTERNAL and EXTERNAL force. I was told by my Professor that there is only internal Torque at the moment when you are running toward a marygoround and grab so of the handles. PLEASE EXPLAIN ME WHY.

Homework Statement Give a specific example of an operator T on R^4 such that, 1. dim(nullT) = dim(rangeT) and 2. dim(the intersection of nullT and rangeT) = 1 The attempt at a solution I know that dim(R^4) = dim(nullT) + dim(rangeT) = 4, so dim(nullT) = dim(rangeT) = 2. I also...

I learned that given a vector space we can construct a basis for it. Can anyone give me an example of this thing (except the trivial example of 2-D and 3-D euclidean space.)

is there a situation where the gravity is negative for example(-0.1) and is it possible i think it is impassible but i have a Friend who believe it is possible so is it possible ? :smile:

I'm looking for a particular (actually, there are probably several) of two numbers that are "extremely close together" - by which I mean they share the first 15 or so significant digits before they differ from each other. I've seen at least one really excellent example of something like...

Assume a weight hanging vertically in a strong, thin and inelastic long cable which is fixed in the top end. The top end cable is then released. When will the mass at the bottom part of the cable start moving downwards?? a) Immediately. In this case information is transferred faster than...

Problem Determine all possible non negative integer pairs (x, y) satisfying this equation: 2^x – 5^y = 3 My Attempt: If x =0, then 5^y = -2, which is a contradiction. If x =1, then 5^y =-1, which is a contradiction. If x = 2, then 5^y = 1, so that y = 0 If x>=3, then we...

I'm wondering if someone can give me an example of an everywhere defined unbounded operator on a (separable for simplicity) Hilbert space in a "constructive" manner. Since it's unbounded, simply a dense definition (i.e. on an orthonormal basis) wouldn't work since you can't extend it by...

Are there any resources on the web that provide example problems (with solutions) to Signals problems? My textbook (shown below) lacks any clear example problems (shows answers without showing you how to get them). If someone could point me toward examples of Convolution, Fourier series, or...

I remember reading a while ago about an animal with a fairly large range. Animals in areas adjacent to each other were genetically similar enough to interbreeed with no problems, but animals from opposite ends of their range could not. I think they existed in semi-isolated populations but am not...

Does anybody knows a textbook, a paper or any lecture notes that discusses the \phi^3 interactive field? I use as main reference Ryder's QFT, which discusses only the \phi^4 interaction. And most similar textbooks (like Peskin's, Brown's etc.) do so. I have derived the point functions and...

Does anybody knows a textbook, a paper or any lecture notes that discusses the \phi^3 interactive field? I use as main reference Ryder's QFT, which discusses only the \phi^4 interaction. And most similar textbooks (like Peskin's, Brown's etc.) do so. I have derived the point functions and...

Please help me, it is my first tym to do Demonstrative project could u post here sites/links where i can see different examples of DP? or just note the sample title of DP please i NEED HELP! THanK YoU!:biggrin:

Homework Statement I have been going through some past exam papers and have come across this vector space question that I cannot find relevant examples for. Consider the vector space V of n-th order polynomials p(x) = a0 + a1x + a2x^2 +· · ·+anx^n, where a0,a1,a2, ...,an are real numbers, and...