Terms Definition and 1000 Threads

Homework Statement I'm trying to express spherical coordinates in terms of cylindrical and vice versa. I would appreciate it if someone could give me some feedback on my attempt at a solution. Thanks for the help! The Attempt at a Solution Spherical(cylindrical) r=(ρ^2+z^2)^(1/2)...

hello! I think it would help a lot to visualize mathematical terms I would like to see the graphs of various f(x), then their f'(x), their f''(x), in order to understand what derivatives mean example: http://en.wikipedia.org/wiki/File:Graph_of_sliding_derivative_line.gif same with...

I just started grad school from an engineering background. My research has led me to need more physics & math which is why I'm in the class, but I don't have a very broad Math background. This problem given is exactly as it is typed above. The text we are using is Arfken: Math Methods for...

I'm trying to work out equation 2.45 in these notes: http://www.damtp.cam.ac.uk/user/tong/qft/two.pdf Anyway \phi(\vec{x}) and \pi(\vec{x}) are given in equations 2.18 and 2.19 When I multiply out \pi(\vec{x}) \vec{\div} \phi(\vec{x}) I get four terms. After normal ordering I can combine two...

Homework Statement "Show that if the Hamiltonian depends on time and [H(t_1),H(t_2)]=0, the time development operator is given by U(t)=\mathrm{exp}\left[-\frac{i}{\hbar}\int_0^t H(t')dt'\right]." Homework Equations i\hbar\frac{d}{dt}U=HU U(dt)=I-\frac{i}{\hbar}H(t)dt The Attempt at a...

'Ello, I have a question regarding the results in this paper (and another which I will mention later) http://arxiv.org/abs/hep-ph/0212199 Now, I'm not so concerned about the 'braney' bit, but more their definition of the cross section in Eqn. (46). They have included the usual (2j+1)...

solve the following equation for z in terms of x and y 3y^{2}+2yz-5z-2x=0 i've spent a lot of time on this question, but i keep getting something along the lines of 0=0 i tried solving for x in temrs of y and z to replace the x but i get 0=0 Homework Statement Homework Equations The Attempt at...

Hi all, I have a summation series which goes like this, S = [log(1)]^2 + [log(2)]^2 + [log(3)]^2 + ... + [log(n)]^2 Since each term is square of the logarithm of a value, I think there are no general tricks which can be used to solve this. But is there any way to approximate the...

Hello Given that english is not my native languagr, can you explain me please these terms and their differences: - function - equation - formula Thanks!

1. (x=X1+vt1, x1=x-vt ) 2.(t=t1+vx1/c2, t1=t-vx/c2 ) I know that 1. is x in terms x1 and x1 in terms of x. I understand it very well, the adding and substracting of velocity. But i am unable to understand the 2.how these equation are derived and what does they mean. The mane...

find no. of terms... Homework Statement find n 212,179,146,113,...... [b]3. The Attempt at a Solution here a=212 d=-33 but nth term or the sum is not given.any help will be appreciated thanks

I noticed that a lot of people simply use flashcards over and over again for studying the terminology of various subjects. Or they just re-read the terms and their definitions over and over again from their notes or textbook. While this can help you study for an exam via cramming, the problem is...

I have been reading this article and google-ing and still nothing, so here it goes What is: -P-type icosahedral? -Tsai-type quasicrystal? -1/1 cubic approximant? -six-dimensional lattice parameter a6D? -why has (this is example) powder X-ray diffraction spectrum just 2 high...

I am 99.5% sure I've got it right, but I keep second-guessing myself. 1] Cube with sides of length X. 2] Diagonals out from each corner of length no less than X... 3] ...to an outer cube of sides of length Y. What must be the (shortest) length of Y in terms of X? I get y = 2\sqrt{2}x

Hi All, Is it possible to express the kurtosis \kappa, or the 4th central moment \mu_4, of a random variable X in terms of its mean \mu = E(X) and variance \sigma^2 = Var(X) only, without having to particularize to any distribution? I mean, an expression like \kappa = f(\mu, \sigma^2) or \mu_4...

I don't know if this is the right forum or not, also, is there a specific forum on ftl travel? But can someone explain Heim theory to a high school student? I know the basics, and how it uses extreme gravitational forces to make the object/ship go to another dimension, where the speed of light...

The use of the terms "speed" & "velocity" This is a interesting topic concerning when to use these two terms in a discussion. Of course, if it is a vector term, then velocity must be used - however even for a scalar term, velocity could still be used. It seems to me that aside from the term...

True or False Questions. I have put my answers to them but one or more is incorrect, can anybody tell me which ones? Note: The linear system Ax=b of m equations in n unknowns is called: square if m=n overdertermined if m>n undeterdetermined if m<n homogeneous if b= 0 inhomogeneous b...

in this picture, there is a legend with the terms LINE and SINE in it http://i.imgur.com/IGJfm.png what do the terms LINE and SINE mean? I mean what do they stand for and what is their purpose in DNA. I have tried to look them up but it keeps going to math.

How would I solve this for x? I've been trying for a while now, and i can't seem to get anywhere. I just need some kind of hint. y=2x-\frac{3}{(2x-4)^2}

Hi, I am currently an undergraduate student of electronics and communication engg. in India. I have been extremely interested in physics since high school. I was planning to go for graduate school in physics. But I read a lot about the job prospects with a physics Ph.D. and considering...

Homework Statement Write the first 5 terms of the geometric sequence 3, __ , 32x+1, __, __ Homework Equations tn=arn-1 The Attempt at a Solution tn=arn-1 32x+1=3r3-1 r2=32x+1 / 3 r=√32x+1 / √3 I'm stuck

33 x 42 __________________________ = 2 x 3-3 x 16 33-(-3) = 6 16 = 42 ... 42-2 = 0 so.. 36 x 2 <-- answer I guess I am not sure

Hi I know that for an airfoil, it's typical to describe stall in terms of angle of attack. I'm wondering, how does Re play a role in flow separation of an airfoil (and for objects in general such as a plate, sphere, or cylinder)? One Wikipedia (http://en.wikipedia.org/wiki/Flow_separation) it...

line integral -- confusion on squares and square root terms Homework Statement Do you see where they have sqrt(16 sin^2t etc = 5? How do they get that, the answer should be 7, the square root of 16 is 4, sin^2 + cos^2 is 1 and the square root of 9 is 3, 3 + 4 = 7. It's like they're...

Homework Statement Find the derivative of (x^2)(sinx)(tanx) Homework Equations f(x+y)(d/dx)=(x)(y)d/dx+(y)(x)d/dx That's for differentiating with 2 terms. With 3, I haven't done it yet. The Attempt at a Solution x^2(sinx)(sec^2x)+tanx(sinx)2x+x^2(tanx)(cosx)...

For expressions like: f(z) = (1+z2)/(1+z4) how does one write the modulus of that in terms of lzl?

Homework Statement Different numbers x, y and z are the first three terms of a geometric progression with common ratio r, and also the first, second and fourth terms of an arithmetic progression. a. Find the value of r. b. Find which term of the arithmetic progression will next be equal to...

Homework Statement Find an approximation of (0.99)5 using the first three terms of its expansion. 2. The attempt at a solution To get to the binomial theorem I divided 0.99 into (0.99)5 = (1-0.01)5 = {1+(-0.01)}5 Then, T1 = 5C0(1)5 = 1 x 1=1 T2 = 5C1(1)5-1(-0.01)1 = 5x1x...

Standard from book: v(t)=K1e^(s1t)+K2e^(s2t) Can I have this below instead? v(t)=K1e^s1 + K1e^s2 - K2e^s3 - K2e^s4 I'm really confused, I sometimes get this when I do calculations. Any ideas? Thanks!

Sorry if this is an obvious question...I understand how the justification via the pressure v temp graph works, but I'm not quite understanding freezing point depression in terms of intermolecular forces and temperature. I was taught that due to attractive IMF between solute and solvent particles...

Homework Statement ##u(\omega) d\omega \propto \frac{(\hbar \omega) (\omega^2)}{e^{\hbar \omega \over k_B T}-1} d \omega ##Homework Equations The Attempt at a Solution ##\hbar \omega ## is the energy of a photon ##\frac{1}{e^{\hbar \omega \over k_B T}-1} ##and this is the density of states...

Homework Statement Express the given vector in terms of its coordinates: The vector from the origin to the end point of the vector from (-3,7,2) in the direction and with the length of u = (2, -3, 4) The Attempt at a Solution I don't even know the algorithm for solving this...

hey guys i want to know the definition of these terms & what are they but please i don't want big words because i won't understand i want to understand it simply: 1-Fermi level 2-Density of states 3-Carrier concentration & the graphs (in the attachment) 4-Mass action law 5-Charge...

Can you please help me find which terms match these definitions: 1. Reflection from a smooth surface in which the angle of incidence equals the angle of reflection. 2. Imaginary line perpendicular to the surface and serves as a reference line for angular measurement. 3. Straight...

The terms "absolute" and "relative" In discussions about relativity I use the term "absolute" as a synonym for "frame invariant" and "relative" as a synonym for "frame variant". I went to look for an authoritative definition and could not find one, so I am a little concerned. Is my usage...

How would i write 1.047 rad in terms of pi? I know the answer i will get is Pi/3 rad, but HOW do i get this answer? I know how to convert degrees to radians and vice versa in terms of pi but this particular question is in radians. Help?

"If we have to take three terms in an AP, it is convenient ti take them as a-d,a,a+d. In general, we take a-rd,a-(r-1)d,...,a-d,a,a+d, in case we have to take (2r+1) terms in an AP." What do they mean by the portion in bold? What is 'r' here ?

Homework Statement Let \vec{R} = (t + \sin t) \hat{i} + (t + \cos t) \hat{j} denotes at time t the position of a moving particle. Determine the radial and circumferential components of acceleration as a function of t. Homework Equations v_r = \dot{r} v_{\theta} = r\dot{\theta}...

So I have read both of the following books Teach yourself physics http://www.amazon.com/dp/1444103091/?tag=pfamazon01-20 complete mathematics http://www.amazon.com/dp/1444105027/?tag=pfamazon01-20 Now I am not sure where to go from here. My goal is to have a firm understanding of...

Can someone please help me figure out which terms match these definitions for nuclear physics? 1. Process in which a nuclide is transformed into a nuclide of a different element. 2. Total number of nucleons remains constant. 3. A radioactive transformation of a nuclide in which a bound...

Homework Statement How many terms has the G.p whose 2nd term is 1/2 and common ratio and the last term 1/4 and 1/128 respectiveley? From the question, it can be deduced that the common ratio, r =1/4 and the last term = 1/128 Homework Equations The Nt term of a G.p = arn-1...

I'm currently studying experiments where one or more factors are random, i.e. random effects models. In this model a professor explained that the Expected Mean Square calculations for any factor are: Expected Mean Square (factor) = (lower level error terms) + (term relating to factor) For...

Without using ' opposite charges of matter' explanation as a foundation for defining anti-matter, I wonder if anyone can present a more direct definition and examples.

Hello, I need help trying to simplify the equation below, I believe it should be in terms of x and constants only, no trigonometry. "Simplify arctan(cot(x)), assuming 0<x<pi/2" After many attempted solutions and failures, my most recent attempt is below. let arctan(1/tanx) = u ==> tan...

Dear all, I have a quantum system made up of two layers. An electric field is applied with two voltages applied at both layers. I want to calculate the electronic densities that reside at the two laters in terms of the wavefunctions obtained from solving the HamiltoniaN..Anyone knows of an...

Homework Statement Find the expected value of cos(A+B) where A is a constant and B is a random variable with a pdf f(b). Present the answer in terms of f(b). The Attempt at a Solution I don't know how far I can go with the answer -- I have tried for a bit now to remove an integral with no...

Homework Statement Find Laplace transformation H(t-1)t^2Homework Equations The Attempt at a Solution [2(e^-s)f(t^2)]/s^3 I'm not sure how to get t^2 in terms of t-1 I know the answer is (2+2s+s^2)/s^3

Homework Statement The problem along with its detailed solution are attached. Homework Equations Inequality, infinite summation and improper integral. The Attempt at a Solution I'm following the solution but I can't justify the first (and only) less-than-or-equal sign. Why is that...

Hi, all I have been reading about copula, but still very confused. What exactly is a copula? My understanding is: there are couple of components 1. uniform cdf marginal 2. a covariance matrix What exactly is this thing? Why am I calculating the marginals and what does it have to do...