Origin Definition and 668 Threads

[b]1. Consider three charges q1 = 4.3 nC, q2 = 6.6 nC, and q3 = -2.3 nC, arranged in a triangle as shown below. (a) What is the electric force acting on the charge at the origin? N, ° counterclockwise from the negative x-axis (b) What is the net electric field at the position of the...

reference in "the origin of species" I've been reading Darwin's "The Origin of Species". It turns out the benefit isn't so much seeing a familiar theory in original form, although there is a fascination in seeing evolution described without knowing Mendellian inheritance. The best benefit is...

New thoughts during my second read of "The Origin of Species"... On humans. Every time I read this book I have new ideas and this one came to me after a second read of Darwin, and another look into the documentary "Homo Futurus". For those of you who have not seen this documentary...

Homework Statement Find a > 0 such that the tangent line to the graph of f(x) = x^{2}e^{-x} at x = a passes through the origin. Homework Equations The Attempt at a Solution First I found the derivative to be: -e^{-x}(x-2)x , which is the slope of the function. I know the tangent line...

The aerial view of Valles Marineras has a strangely familiar look to it. As a kid I would shoot BB's at all sort of fruit and mud and stuff. Sometimes I'd hit a rotten apple or tomatoe with a glancing shot that would rip open a gaping tear for a distance as the BB would enter, force material out...

I have a problem that I've been unable to find a simple solution for. When solving Schroedinger's equation for a central force, the nonradial part of the solution can be found with spherical harmonics, but the radial part is much more difficult. E\psi = -...

Hello! I'm looking for information, articles and theories about which could have been the original molecule of life: DNA, RNA or protein. Most of what I've found is based on the RNA world theory (which I think is pretty well explained and sounds plausible), but I haven't found out any...

I have to say a lot of the physics discussd in this section is a little beyond me but that does not stop me thinking. Given the search for the Higgs Boson which allows mass to exist it has occurred to me what is the origin of the electric charge. Surely as mass is property with an origin what...

Please teach me this: What is the origin of mass of both fermions and bosons?Is it correct that the origin is the spontanious broken symmetry of Higgs Field?(I know that Higgs mechanism is the origin of mass of vector boson W and Z in weak interaction). Thank you very much for your kind helping.

hi i was wondering whether the lorentz force is just caused by the fact, that moving charges produce a magnetic field, just like every current does, and this magnetic field interacts with the magnetic field in the environment, that causes the force or whether the lorentz force has nothing to...

The Attempt at a Solution I could not figure out the first part, though i know that distance is λn, λ being any non-zero scalar. But i could not figure out the first question it self.

We've just learned about kinetic theory and gases and my teacher showed us the rms speed. He himself doesn't know why its called the rms speed, or how it originated and I was curious to find out myself. Why go through all the trouble when you could just say the average speed? If anyone could...

Homework Statement find the equation of the line through the origin and with angle of inclination tan inverse 5/7 Homework Equations The Attempt at a Solution

Homework Statement If you have a point at x = c and a function f(x), then I know Δy = f(c + Δx) - f(c). Also, dy = f'(c)dx. However, I am uncertain of the origin of dy = f'(x)dx. I want to say: f(c + Δx) - f(c) = f'(c)(x-c) was simplified to dy = f'(c)dx where f(c + Δx) - f(c) = dy...

Homework Statement Find the point(s) on the surface z2 - 10xy = 10 nearest to the origin. The Attempt at a Solution I will minimize distance by minimizing distance2. So, D = x2 + y2 + z2, where z2 - 10xy = 10. By Lagrange multipliers I have, 2x = -10yλ 2y = -10xλ 2z = 2zλ. By the last...

Homework Statement Draw the phase portrait and classify the origin of the system: xdot = [1 2; 2 1]x Homework Equations characteristic equation: det(A-lambda*I) = 0 The Attempt at a Solution First find the eigenvalues and eigenvectors: det(A-lambda*I) =...

Please teach me this: Can we deduce Ward Identity in QCD from U(1) symmetry of QED?Because QCD is a theory of quarks and quarks have electric charge.So we need not deduce the Ward Identity from SU(3) symmetry,but we can be able to demontrate the Ward Identity( considering gluons)with U(1)...

The origin of our Universe (i.e. the Big Bang) is often considered as an explosion in static 3D Euclidian space: http://youtu.be/R2Zi_z4n4c0 I think the Big Bang is somewhat of a misnomer. It’s not an explosion in static 3D Euclidian space. If this was the case, then it would difficult...

Hi there. I have a problem with this. I'm trying to plot a polynomial fit done with origin 8.5 on mathematica. The thing is that the polynomial plot I get in mathematica from the coefficients given in originlab don't match, and I don't know why. I'll let you some pics of what I'm trying to do...

I'm just thinking that the fabric of space reminds me of oil on water in my kitchen sink. If the universe itself started in an equilibrium and a random force bounced into this substance just like adding your favorite dish soap to the water. the oil automatically starts to gather create eddies...

If the universe was smaller than a proton before the big bang, can we say that the question of the cause of bigbang is meaningless (i.e. it happened without any logic)? I say this because sub atomic particles keep on popping in and popping out of existence without any underlying cause. Or is...

Homework Statement 1. Find all the points P_{0} on the surface z = 2 − xy at which the normal line passes through the origin. Homework Equations The Attempt at a Solution See the photo. It seems as long as I can find a,b and c, then the question is done. However I don't know...

If you talk with Jews who don't keep Kosher, but follow other aspects of the faith, they will often excuse their not being Kosher with something like this: ''Well, those laws don't really apply to modern times. Back then, it made good sense to avoid eating pork, it was more dangerous to eat...

what is the origin of a neutrino? from which part of the atom it comes?

I'm a little very confused about the origin of surface tension. As I understand it, surface tension is a force on the surface of a liquid which is directed parallel to the surface, correct? But the explanation of surface tension is that molecules at the surface are not covered by other molecules...

1. A Ball is in a frictionles tube that is rotating with a constant angular velocity \omega. The ball is initially held in place a distance r0 from the pivot by a string which breaks at t=0. If the radial coordinate of the ball from the origin is r(t), find r(t). I am having a very hard to...

Hi guys I posted a picture of the problem set and my work so far. I am on letter (d) of the problem set and I am stuck. I am 90% sure I have the formulas to solve (d) through (g) but I am not clear how. Can anyone give me a basic idea on what step I should take next? Problem set my work...

Question: Find the distance from the origin to the line x=1+t, y=2-t, z=-1+2t Equations: r = r0 +tv Attempt: I think I solved for the vector line equation correctly: r = < 1, 2, -1> + t< 0, -1, 2> But I don't know where to go from there. Help please!

Hello! If you do a plot in Mathematica, for example Plot[Sin[x], {x, -, 2 Pi}] it won't put zero near origin of coordinates. So how can do it ? I tryed actually AxesOrigin or smth like that, but it didn't help me. Thanks!

Homework Statement Find the distance from the origin to the line x=1+t y=2-t z=-1+2t Homework Equations Possibly d=|aXb| / |a| The Attempt at a Solution I think I need to use the formula provided above, but I'm not sure how. A different distance formula was covered in class...

Hi, Does anybody know how I can let Mathematica show the origin point when plotting? Usually, it labels the axes with numbers but not the origin. I have to use Tick{} to let it show origin. But who knows how I can have it show automatically? Thank you.

Homework Statement Consider two points located at r1 and r2, separated by distance r=(r1-r2). Find a vector A from the origin to a point on the line between r1 and r2 at distance xr from the point at r1, where x is some number Homework Equations The Attempt at a Solution I have no...

Please teach me this: It seem that the ultraviolet divergence has origin of we unknow the physics at very small distance(very large momentum,then very small distance).So we must cut off the very large momentum by renormalization procedure.But I do not understand the origin of infrared...

Find an expression for the distance between the origin and the line L given by r = p + tv, where t is an element of R and determine the point on L closest to the origin So the first part of the question i took as just the magnitude of p since the distance will just be...

Homework Statement Point charges +q and -q are placed at +50 cm and -50 cm on the x-axis, respectively. Is the electric field at the origin (halfway between the charges) zero or nonzero? If nonzero, which direction does it point? Homework Equations The Attempt at a Solution If...

Homework Statement In the derivation of the momentum operator: Why is this equal? Homework Equations [PLAIN]http://img268.imageshack.us/img268/4575/momentumoperatorderivat.png The Attempt at a Solution I thought maybe the integral is executed, but the integral sign stays. One p...

So i have jut finish watching BBC Horizon Documentary about What happen before big bang. Documentary raises more question then answers. So i suppose main theory goes like this: there was nothing and then at some moment, for what ever reasons, there is a huge explosion and universe comes to...

Time had a beginning. It began with the original motion. Something caused things to move. Before motion time did not exist. No speed existed. No dimension existed. No e = mc^2. No form of energy existed. The original motion, like all motion that followed cannot be duplicated, so...

Hi! I came across the concept of endosymbiosis being the way by which eukaryotic cells evolved and that all cell organelles are remnants of prokaryotic cells that lost their ability to survive independently. Is this just speculation or is there a solid scientific basis to this claim? Can anybody...

Homework Statement Well, I'm not sure if this is a correct subforum to post my problem, but to me it does seem to me as an academic problem. One I can not solve, apparently. Well, anyway. I'm solving the 1+1 radial wave equation using finite difference. I shifted my grid, so that the origin...

A student showed me a problem, this week, it was: What is the number of regular polygons whose intern angle is an integer number? I used the equation i=180 (n-2)/n, where i is the internal angle of the polygon and n is the number of the sides of the polygon. After some trials, i got to the...

Does anyone know who first posed the energy relation E2=m2c4+p2c2 and where its original appearance can be found?

I have to give a brief presentation on the evidence for pairing in atomic nuclei. One of the items of evidence I will talk about is the difference in binding energy between even-even and odd-odd isobars. For instance, here I have plotted the atomic masses of a range of even-A isobars A = 40...

My understanding of the origin of matter is that it arose from pair production after the big bang. The process leading to electrons also produces an equal number of positrons. The universe now has lots of electrons and essentially no positrons. Since positrons are inherently stable, I presume...

Homework Statement You have a semicircle of radius R and charge Q. We also have available a test charge +qo. Find the Magnitude and direction of the electric field at the origin. Homework Equations Electric Field: F = k (Q * qo)/(R^2) E = F/qo = kQ/R^2 The Attempt at a Solution...

Hi everyone. I am a new member and I'm not sure where this question belongs, but it is interesting nonetheless. I was just introduced to vector-valued-functions of surfaces and 3-D objects. My question is this: What real-world benefits are there of changing the origin of a vector-valued...

Can anybody tell me the significance of the band origin for a P(Q)R structure in the ultraviolet region of a molecules spectrum? In standard vibrational spectra, I understand that its roughly the harmonic frequency of the oscillator, and that the rotational constant can also be found from...

This is part of the problem in the exercise to find charge distribution of a point charge at origin. I know \nabla \cdot \vec E = \frac {\rho}{\epsilon_0} \rho = \epislon \nabla \cdot \hat r \frac q {4\pi\epsilon_0 r^2} \;\hbox { where } \vec r = \hat x x + \hat y y + \hat z z \nabla...

Hello, I'm a newbie so please tell me if I'm doing anything wrong :) I am working on a portfolio for school and I have chosen the topic "Air". As I was all set and ready to start, I realized that I didn't know the first thing about air. By now I know that what we call "air" is in fact the...

Homework Statement Determine the magnetic field (in terms of I, a, and d) at the origin due to the current loop shown in Figure P30.14. (Use mu_0 for µ0, pi for π, a, d, and I as necessary.) http://www.webassign.net/pse/pse6_p30-14.gif Homework Equations B=mu_0(I)/(2pi*r) for straight...