Position Definition and 1000 Threads

Homework Statement Give two reasons why the apparent position of the Earth's geomagnetic pole, as recorded by ancient rocks, may not correspond to its present position. The Attempt at a Solution Continental drift? So what is recorded by ancient rocks is not totally accurate because it...

Homework Statement given the following position vector: R = (10n1 + 9n2 + 19n3)(a/10) x + 6(n2+n3)(a/5) y + 2(n3)a z where n1, n2 and n3 are integers Find the primitive lattice vectors. Homework Equations any position vector of a lattice point is of the type R= c1 a1 + c2 a2 + c3 a3; and...

And visa versa. And I'm only in 9th grade, so please don't give me any complicated answers or links. I just want to know simple stuff like, "If there is a straight horizontal line in a velocity vs. time graph, how would that look like on a position vs. time graph?" Basically, I just want to know...

Homework Statement a particle traveling in a straight line is located at the point (4, -2, 3) with the speed of 2 m/s at time t=0. the particle moves toward the point (6, 0, 9) with constant acceleration 3i-j+k. find its position vector r(t) at time t The Attempt at a Solution...

How does on calculate the expectation of the position operator x in a 2D infinite potential well (in the xy plane)? Do we only work with the Psi to the Hamiltonian in that particular coordinate when finding <Psi|x|Psi>?

Homework Statement A one-dimensional force acts on a particle of mass m = 6.26 kg in such a way that its position is given by: x = 0.484t^3 - 33.6t Find W, the work done by this force during the first 1.49 s. Homework Equations W=F*s W=mgs Integration The Attempt at a...

Homework Statement Show dT/dx = ma Homework Equations T=1/2mv^2 F=ma The Attempt at a Solution dT/dx = d/dx(1/2mv^2) = mv.dv/dx <--------------i believe you use the chain rule. But can someone explain exactly how to get to this step? = mv. (dv/dt)...

Homework Statement A one-dimensional force acts on a particle of mass m = 6.26 kg in such a way that its position is given by: x = 0.484t3 - 33.6t Find W, the work done by this force during the first 1.49 s. Homework Equations F=mg F=ma W=F*distanceThe Attempt at a Solution To find the...

Homework Statement A particle has a linearly varying rectilinear acceleration of a=x''i=(12t)i m/s^2. Two observations of the particle's motion are made: Its velocity at t = 1s is x'i=2i m/s, and its position at t= 2s is given bt xi=3i m. (a) Find the displacement of the particle at t=5s...

Reason I posted this in the maths help forum is that an equation of this form randomly popped up in a homework I was doing on differential geometry. I started with a one-form ω=dβ (β is a scalar function) and found that if for a random vector v, ω(v) = 0, then \frac{d}{dt} \left(...

In quantum mechanics, the Hamilltonian operator is constructed as the infinitesimal generator of the time translation group, which is a 1-parameter group. Yet it can still depend on time. So you have a situation where the generator of a 1-parameter group can depend on the parameter. Yet the...

Homework Statement A 2.40 kg particle moving along the x-axis experiences the force shown, where Fmax=6.41 N, Fmin=-6.41 N, d1=1.77 m, d2=3.54 m, d3=5.31 m, and d4=7.08 m. At x=0.00 m the particle's velocity is 4.54 m/s. What is its velocity at x=3.54 m...

Finding a position vector... Homework Statement A spaceship is traveling with acceleration a(t)=<e^(t) , t , sin2t>. At t=0, the spaceship was a origin r(0)=<0,0,0> and had an initial velocity of v(0)=<1,0,0> Find the position of the ship at t=piHomework Equations uhhh... The Attempt at a...

suppose I have two position functions in terms of time. One position function for the x component and the other for the y component. The y component is of constant acceleration. The x component is of constant velocity. How do I represent acceleration on a graph of this type? Here is an...

Position and acceleration vector -- parallel and perpendicular Homework Statement The motion of a particle is defined by the position vector r = A(Cos t + t Sin t) i + A(Sin t + t Cos t) j where t is expressed in seconds. Determine the values of t for which the position vector and...

Hi English is not my native language and I have these type of questions all the time. I would like to know if the terms Linked and Opposed are correct when one wants to talk about the position of two vertices relative to a quad for example, as in: "Vertices A and C have an Opposed Relation."...

I used an online simulation for this lab. Mass: 1.0 kg Force: 1 N X position: – 2 Y position: 0 The final position was 6.0, final velocity was 4.0, and final time was 4.0 At 3 seconds the position was at 2.50 and velocity was at 3.00 Because I used an online simulation I...

If acceleration is a function of position, can you express velocity as a function of position, or would there have to be a time variable? For example, if F = kx = ma, and v0 is given, then a = (k/m)x, so what would the function for v be? I would think that, if you know the acceleration at...

Homework Statement Given an isosceles triangle - Length = L - Uniform Density = ρ - Width Varies from 0 at x = 0 to a at x = L I attached a picture of it. Homework Equations Have to show the width at position x is given by (a/L)x The Attempt at a Solution Now it is...

I have a question about this problem in relation to the way the solution manual handles it. Homework Statement A force Fx acts on a particle of mass 1.5kg. The force is related to the position x of the particle by the formula Fx = Cx3, where C = .50. IF x is in maters and Fx is in...

Hi everyone, Quick question I may just not be thinking right here but I was trying to find the acceleration, velocity, and position of a rocket as a function of time. I started with acceleration: a =\frac{T}{m-\dot{m}t} - g where T is the Thrust, m is the initial mass, mdot is the mass flow...

Hello everyone, I need some help, which I would be very grateful for. My local council, here in the UK, are looking to employ someone who they will train, as well as send the successful candidate to a local college/university to gain HNC level in Information Communications Technology. This is...

Does anyone know anything more about this position other than what is posted on the CIA website? https://www.cia.gov/careers/opportunities/analytical/science-technology-and-weapons-analyst.html

Homework Statement Write an equation for one component of the position vector as a function of the radius of the circle and the angle the vector makes with one axis of your coordinate system. Calculate how that angle depends on time and the constant angular speed of the object moving in a...

Homework Statement Suppose that a neutron with with mass M and initial speed v0 is traveling through a material, such as graphite. As the neutron moves, it makes collisions with atoms in the material, so teh faster it is moving, the more collisions it makes per unit time. Another model of...

So i made up this simple setup: I have a √(2) meter stick slanted on a friction-less surface on a 45° angle. And i want to determine the final x and y positions of the points A and B. For point A: A.1) Solving for ax \sum F_x = T_x = F_xTcos(\theta) = ma_xa_x = \frac{Tcos(\theta)}{m} A.2)...

Ok so I have my AA in General Studies, Science Emphasis and I applied for and have scheduled an interview for a job entitled Science Lab Tech out at my local community college where I graduated. I know the interview will be with a commity and I have been told that I won't be able to fake any...

Homework Statement Give the velocity v = ds/dt and initial position of a body moving along a coordinate line. Find the body's position at time t. v = 32t - 2, s(.5) = 4 The Attempt at a Solution Here's how the solution manual does it: step 1. v = ds/dt = 32T - 2 step...

I use the planetarium program The Sky quite a bit. It's capable of showing the sky from -4700 years ago to 10000 years into the future. What's the methodology behind this? One giant leap, or small leaps of say 100 years to get there, with some last jump to the final date?

I was wondering why when we derive the euler lagrange equations and when we use them we treat x and x dot as independent quantities?

From what little I have read about QFT, apparently the position of a particle is not a observable - it is more like an index for a collection of quantum harmonic oscillators. Thus there is no QFT equivalent to the position probability density in QM. So, how does QFT predict or describe a...

Homework Statement Consider a rigid sphere of radius 1 and center at (0,0,0) that rotates about its center. The angular velocity is $\omega(t) = (\cos(t) , \sin(t), \sqrt(3))$. Does the path of the point starting at (0,0,1) ever reach this point at a later time? Homework Equations...

Difference between "Position Vector" & "Displacement Vector?" (no calculatins..) http://en.wikipedia.org/wiki/Position_(vector ) http://en.wikipedia.org/wiki/Displacement_(vector ) Is the position vector simply an initial vector given by coordinates (x,y) or (x,y,z) such as (8,4) or...

Hi, So I applied for a postdoc position for a research lab in France. In my cover letter to the PI (who's English) I wrote at the end: "I will call you next week to make sure that you received my CV. Thank you for your time and consideration." I received an acknowledgment of my application...

We know that the universe is expanding,but do we know from which point it is expanding outwards?

A circuit has a 10 kΩ potentiometer with a 5 kΩ load. Determine the position of the slider on the ‘pot’ when the voltage across points ‘XX' is 3 V. Think I'm there but not sure of my working out is excessive or I've taken the long route R1 in series with 2 resistors in parallel (R2 and...

Derivative: position, velocity, acceleration as functions of time? Homework Statement A 1.00 kg glider attached to a spring with a force constant of 25.0 N/m oscillates on a frictionless, horizontal air track. At t = 0, the glider is passing through its equilibrium position with a velocity...

Hi everybody, I'm planning a 2016 mission to the moon similar to Apollo 8 (Orbital mechanics homework). I decided to start from a equatorial parking orbit, and then to perform a plane change. The problem is that I obviously need to know the position of the moon's orbit plane, which, as you know...

.. Using Keplerian Elements Hi. Disclaimer: this is the first foray into orbits I've ever taken. I only did mechanics in university and haven't really touched it sincew. I'm busy coding a simulation of a solar system. I've managed to code a routine to calculate the position of a body along...

In what kind of cases do u we formulate the equation type x=Asin(wt+phi) or x=Acos(wt+phi)...and if for example we use it to define the position of some thing in motion when do we know when to use cos and when to use sin...?

The first thing I remember hearing about in QM was the time-independent 1-D schrodinger equation, Hψ = (\frac{-\hbar^2}{2m}\frac{d^2}{dx^2} + V)ψ(x) = Eψ(x) . This is an eigenvalue equation, the Hamiltonian operator H operating on the energy eigenstate ψ to produce the product of the energy...

Homework Statement Using the position space representation, prove that: \left[L_i, x_j\right] = i\hbar\epsilon_{ijk}x_k . Similarly for \left[L_i, p_j\right] . Homework Equations Presumably, L_i = \epsilon_{ijk}x_jp_k . \left[x_i, p_j\right] = i\hbar\delta_{ij} . The Attempt at a...

I'm looking at some code from a book that details uses the heliocentric position and velocity to compute an orbit of a meteor. See attached pages. At the top of the section at mid-page, page 37, he gives a source, Herget, 1953, Solar Coordinates 1800-2000. The book was written in the...

Homework Statement Give expressions for computing the matrix elements Xmn of the matrix X representing the position operator X in the energy basis (using eigenvectors of the Harmiltonian operator) Also told to consider the example of the harmonic oscillator where energy eigenvalues are...

I'm designing a 4-layer board with a couple of CPLDs and a uC. The top and bottom layer are for signals and the 2nd layer is ground and the 3rd layer is 3.3V. I'm placing a 0.1uF X7R Ceramic cap in 0402 package on every Vcc/Gnd pair. The thing that confuses me is that I've seen several ways...

Homework Statement The circuit (attached) shows a 10kOhm potentiometer with a 5 KOhm load. Determine the position of the slider on the 'pot' when the voltage across points 'XX' is 3V. Homework Equations Vout = Vin* (R2/(R1+R2)) The Attempt at a Solution Please see attachment...

Hello! Not sure if this should go here, but it's from a physics textbook. I was reading about charge by induction and the use of an Earth to achieve this. Here's a wonderfully detailed and exquisite image that took many laborious hours to construct. The red and black Earth's are not intended...

I would just like some clarification and some assertion that I've got the right idea. Please correct everything I say! For any observable A over a finite-dimensional vector space with orthonormal basis kets \{|a_i\rangle\}_{i=1}^n we can write A = IAI = \left(\sum_{i=1}^n |a_i\rangle\langle...

Homework Statement A simple pendulum consists of a bob of mass 1.8kg attached to a string of length 2.3m. The pendulum is held at an angle of 30° from the vertical by a light horizontal string attached to a wall. If the horizontal string is cut close to the bob and the pendulum swings down...

Hi, I'm trying to calculate a postion and velocity of a body over time using an integrator at each time step, I've only used simple integrators so far but I wanted to a better one that I've seen, RK4 - Runge–Kutta method, to calculate new values of position equation. I've been using the...