Component Definition and 568 Threads

What does "couples as the 4th component of a vector" mean in the Dirac equation? I'm doing an exercise regarding the spin-orbit operator and the Dirac equation/particles, and I'm having trouble understanding the link between terminology and mathematics. The particular phrase I'm having trouble...

I'd like to know how do i find I2 (Negative sequence current) if I know Ia, Ib and Ic but don't know angle (in normal system_not fault)? My system's 3 phases 3 wires.

Angle of vector in component form Find the vector's magnitude and direction. Use right as the +x direction and up as the +y direction. \vec{A} = 3.50 \hat{i} - 7.70 \hat{j} Find \theta_A degrees below the positive x-axis. \theta_A = arctan\left ( \frac{7.70}{3.50} \right )...

Hi everyone, This appears to be a trivial question but I'm uncertain to the correct answer. If I have forces of 3N, 4N and 5N in the x,y and z directions respectively. The resultant force will be the square root of these components squared ≈ 7N. If I want to describe any of the components...

I am developing a simple probabilistic model of my own mistakes in (1) solving math problems and (2) implementing algorithms on a computer. I have reduced the problem to one which seems simple enough, but which I have been unable to solve, due to my mathematical inexperience. I figured I would...

Hello, we are learning about single balanced and double balanced modulators. Apparently single balanced modulators include an information, upper and lower sideband component while double balanced modulators use only the upper and lower sideband components. Can someone please tell me why the...

The test question was... We are given a region bounded by the functions √x and x. We were also given the density and mass of the region and asked to only the component y of the centroid. I did not know how to implement these given variables, density and mass into my equation for y bar so I...

I have a 100watt xenon lamp , the UV component comprises of 5-6% of the total spectrum emitted by the xenon lamp . How do I calculate at what power is the UV light emitted ? Is the whole spectrum being emitted at 100 W or is the power distributed through the spectrum? How is this...

I have two questions: Pic 1: An object is placed on top of a spring scale which strapped to a horizontal surface. They slide down on an incline of 30 degrees. Friction is ignored. What fraction of the weight does the spring scale read of the top object? (Only incline is given, and friction is...

There is the problem which i haven't been able to understand: "Show that the tangential component of an electric field is continuous from one side of a conductor to the other" What exactly is asked and how to prove it? Thanks!

Homework Statement A ball travels vertically upward with quadratic air resistance, find the acceleration component. Homework Equations So, I have x pointing vertically downward and C=0.20 D = Diameter V=velocity W= -mgi R = -C^2D^2V^2 F=ma ma= -mg-C^2D^2V^2 The...

Hi, I am having a little bit of difficulty rotating an assembled component in SolidWorks. I have followed the help file to the letter and for some reason the component is not rotating as expected. I have rotated it using the Triad method described and also by selecting the component and moving...

Hello all, I have an amplifier in mind, you could think of it as an ac coupled differential amplifier, where the coupling capacitance is extremely small (<1pF) and you can assume the input is a sinusoidal differential voltage function. The amplitude of the source is over 1 Million volts...

Hi all, first post here! Homework Statement Find the x component of acceleration. Find the y component of acceleration. The mass of the particle is 2kg. Homework Equations The Attempt at a Solution I've only tried to find a_x. I thought that for finding component values you need to add...

Hi all, Here's a particular procedure to deal with the giant component of a random graph. Is it "almost always" as efficient as experiments suggest? If so, can you shed some light as to how the giant component evolves under this procedure? Suppose we're given a large graph with a large...

This question was just given on a CEE 270 exam (handwritten by professor). The way it's written doesn't make any sense to me. Homework Statement A force vector \vec{F} = (70.0 \hat{i} + F_{y} \hat{j} + 140.0 \hat{k} ) N has a component of +20.0 N in the direction defined by the vector...

When I'm reading a tutorial about Harmonic Balance algorithm (this is a link to the tutorial website), I'm quite confused by the concept it mentions about the nodal analysis of non-linear components, especially for: The non-linear circuit is modeled by its current function i(t) = i(v_1...

Hi there everyone, This is my first post here. I'm a musical instrument maker who also dabbles in robotics and electronics as a hobby. I need some help identifying a mechanical component. It's in two parts, a plastic internally threaded housing and an externally threaded insert that screws...

Homework Statement An a.c. voltage, V, comprises of a fundamental voltage of 100 V rms at a frequency of 120 Hz, a 3rd harmonic which is 20% of the fundamental, a 5th harmonic which is 10% of the fundamental and at a phase angle of 1.2 radians lagging. (i) Write down an expression for the...

Homework Statement Find y component of vector C from its length and the angle it makes with the x axis, that is, from geometry. Express the y component of vector C in terms of C and \phi. Homework Equations Vector addition using geometry: 1) C = \sqrt{A^{2}+B^{2}-2ABcos(c)}...

I'm wondering if there's a term for the property of spheres that makes gravity pull equally on all aspects of the sphere's mass. The wording for what I'm asking is tricky, so I'll give an example of a shape that wouldn't have this property, a long prism. If you drop a long prism on an angle...

What is this electrical component "CR"? Hey folks, Can anyone give me a hint to what the CR symbol in this wiring diagram might mean? I'm thinking it is some kind of switch... The equipment is a solar cell tester. Basically it traces I-V curves. In the attached picture the pins...

Homework Statement Resolve the position vector A of the car (measured from fixed point O) into components parallel to OB and OC. Figure: http://screensnapr.com/e/4D2OAz.png Homework Equations Projection of vector A to OC = |A| * |unit vector OC| * unit vector The Attempt at a...

I have a theory described by a 2-component field \psi_i (i'm working with BCS in Nambu-Gorkov representation, but any other field theory would be ok, that's why I'm posting in this subforum), and the lagrangian it's defined in the following way: \mathscr{L}=\psi^\dagger \Gamma \psi where...

Hello i know how to derive the components of acceleration in other coordinates like spherical start here : http://up.iranblog.com/images/0mbwuclckbu51bxt8jfa.jpg and at last we have : http://up.iranblog.com/images/geotowiaxdya2s6ewxk.jpg also , i know that acceleration is a contravariant...

I'm sure this question gets brought up a lot, but I can't figure out why this is true. Everywhere I look, people simply equate the two as though it's some axiom, but never an explanation for why. It seems to me like E≠m/√(1-v^2) in general.

I am designing a car engine water pump and I want to know where i can find the standards of engine components that i can relay on. I mean what safety factors of stresses ,pressures temps and so on need to be accounted for.

Homework Statement given a certain state |ψ> that is an eigenstate of L^2 and Lz Calculate <Lx^2> and <Lx> Homework Equations L^2|ψ> = l(l+1)h^2 Lz|ψ> = mh|ψ> Lx = YPz - ZPy The Attempt at a Solution <Lx^2> = (1/2)(h^2)[l(l+1)-(m1)^2] for Lx i got <Lx> = ∫ψ(YPz-ZPy)ψ dx

This might be a very stupid question but I can't come up with an answer, I hope you might help. So, I have two vector in a 3D space \vec x and \vec x^\prime. I know that a certain quantity \vec a is defined along the radial direction between the first vector with respect to the second. What are...

I was thinking about gravity, and it seems strange that point masses really work, one question, since I am not that great with relativity is: does GR take density into account? For instance in Newtonian gravity, the distance from the planet's surface doesn't make a difference, it seems in the...

Problem - Given the following table x y 15 50 26 46 32 44 48 43 57 40 a) Find the sample mean b) Find the covarince matrix c) Perform principal component analysis and find a size index which explains the greatest variation. My attempt a) n = 5 xbar = Sum(x)/n = 35.6 ybar =...

For example, suppose you have some data where each point takes its value from U(0,1) with probability p and the Cantor distribution with probability (1-p) where p is fixed but unknown. Here the standard MLE approach falls over, so how would you go about estimating p?

an Anaeroplane is flying in the direction 10 degree east of south at 600km/hr.find the component form of the velocity of the airplane assuming that +veX axis represent due east & +ve YaxisRepresent due north

If you have a falling object and wind in the horizontal direction, the object ends up falling to the ground at an angle. Why does the drag force only have a vertical component? Thanks!

Hi, I wish to listplot a list object against a scale that is NOT the component number of the vector, but is actually a well defined function of the component number, and I am lost how to do this? changing "Ticks" didn't help, or I did it wrong, so I am wondering if anyone knows how to do this...

Homework Statement Show that radial components of the continuum electron wave function satisfies the radial equation: {\left[\frac{-\hbar }{2m}\frac{1}{r^2}\frac{\partial }{\partial r}\left(r^2\frac{\partial }{\partial r}\right)+\frac{\hbar ^2l(l+1)}{2m r^2}-\frac{Z e^2}{r}\right]R=E R}...

If u have conducting spherical which is not hollow. We know from guass law that the outter component is experienced electrical force from the inner component. But why the inner isn't experienced the force from the outter. Please show and proof it in mathemetic and describe in the qualitative...

A ball of mass 0.6 kg, initially at rest, is kicked directly toward a fence from a point 20 m away, as shown below. The velocity of the ball as it leaves the kicker’s foot is 17 m/s at angle of 52◦ above the horizontal. The top of the fence is 7 m high. The ball hits nothing while in flight and...

Why is it that the Energy of a system is identified with p_0 and not p^0? This is especially concerning to me in non-Minkowski metrics, such as the Schwarzschild metric, where the difference between p^0 and p_0 can be quite dramatic. In the schwarzschild metric, we have: p_0 = -\tilde{E}\,m...

Apostol in his "Mathematica Analysis" defines something called a "component interval". However, I cannot find it anywhere on google or in other books I have on analysis, and I really would like to see a picture of what he means.. Apostol's definition is that the component interval of an open...

Homework Statement A 76-kg crate starts from rest at A and is moving at 8 m/s. Using integration, find the work done between A and B of the variable x component of force F= 756 N. (See attached jpeg for the geometry of the problem) EDIT: We are doing a variation of the problem shown in the...

Homework Statement Find a basis for the orthogonal complement of the row space of A: A = [1 0 2 1 1 4] Split x = (3,3,3) into a row space component xr and a nullspace component xn. The Attempt at a Solution For the first part of the problem I took A to RREF R = [1 0 2 0 1 2]...

I am reading a paper and the authors read the tt component of the metric from the line element ds^2=f(r)[g(r) dt^2+h(r) dr^2] as g_{tt}=g(r) instead of (what I expect to be) g_{tt}=f(r) g(r) Could somebody please explain to me why? Thank you.

[b]1. A 0.20kg ball with an initial velocity of (26i-1.6j)m/s collides with a vertical wall. The wall exerts a constant force of -175i N on the ball and the ball's final horizontal velocity component is -15i m/s. Find the final vertical velocity component of the ball. [b]2. I know how to...

Hi all I hope you can help I'm really racking my brains about this! The question simply states that a cannonball is fired over a wall 40m away and passes directly over the wall at a height of 15m. Find the vertical component of velocity? I've been searching the net and apparently when V...

I'm trying to follow the math in Wald's General Relativity where he starts out with the equation for covariant derivative: \nablab\omegac = \partialb\omegac - \Gammadbc\omegad He uses that to derive the equation for a double covariant derivative: \nablaa\nablab\omegac =...

Homework Statement A jetliner is moving at a speed of 233 m/s. The vertical component of the plane's velocity is 66.9 m/s. Determine the magnitude of the horizontal component of the plane's velocity. The Attempt at a Solution 233m/s^2=66m/s^2+x^2=233.189135m/s 66m/s cos(90)=0 I am...

Two geological field teams are working in a remote area. A global positioning system (GPS) tracker at their base camp shows the location of the first team as 38 km away, 19° north of west, and the second team as 29 km away, 35° east of north. When the first team uses its GPS to check the...

For -\frac{1} {4} F_{\mu\nu} F^{\mu\nu} We can write -\frac{1} {4} F_{i j} F^{ij} -\frac{1}{2}F_{0i} F^{0i} Where F_{\mu\nu} \equiv \partial_\mu W_\nu-\partial_\nu W\mu If there are 3 indices how can I separate them like this? I want to separate \frac{1} {12} G_{\mu\nu\rho}...

Homework Statement Consider the two vectors A=ai and B=3i+4j. What must be the value of a if the component of A along B is 6? Homework Equations The Attempt at a Solution I've arrived at the correct answer by finding the angle between the x component of B (3) and B itself which...