1d Definition and 383 Threads

Homework Statement To find the height of an overhead power line, you throw a ball straight upward. The ball passes the line on the way up after 0.70 s, and passes it again on the way down 1.2 s after it was tossed What is the height of the power line? m What is the initial speed of...

Homework Statement 1D polymer, fixed segment length a If the angle between segment j and j+1 is 0, the energy is 0 If the angle is pi the energy is +2J. Compute the correlation function <s_i s_{i+n}>, where s_j = \pm 1 denotes the direction of segment j Find the persistence length Lp...

Hi! I read that in an 1D potential, the solution for the Schrödinger equation is always either symmetric or antisymmetric if the potential is a symmetric function: V(x) = V(-x). How can I proof this? Thanks, for ur answers!

The solution to the diffusion equation in 1D may be written as follows: n'(x,t) = N/sqrt(4piDt) * exp(-x^2/4DT) where n'(x,t) is the concentration of the particles at position x at time t, N is the total number of particles and D is the diffusion coefficient. Write down an expression for the...

INTRODUCTION: This is a problem from my Introduction to Physical Science class using "Conceptual Physics" 10th Ed.by Paul G. Hewitt EXACT PROBLEM: "The coefficient of kinetic friction between a rubber tire and a wet concrete road is 0.5." PROBLEMS FACED: a) Find the minimum time in...

A motorist is traveling at 18 m/s^2 when he sees a deer 38 m ahead. If the maximum negative acceleration is -4.5 m/s^2, what is the reaction time (delta t) of the motorist that will allow him to avoid hitting the deer? Answer in units of 's'. I tried using x(t)=x0+v0t+1/2at^2 and it didn't...

Consider the one dimensional motion of a particle in the potential V(x)=D(e^{-2ax}-2e^{-ax}). I'm supposed to obtain the expressions for x as a function of time separately for the cases that the total energy E is positive, zero or negative. I have used \frac{1}{2}m\dot{x}^2 + V(x) -...

Question states: Derive an expression for the energy of the bound states of a particle in the one-dimensional well defined by: V(x) = \infinity x<=0 (Region I) V(x) = 0 0<x<L (Region II) V(x) = V_0 x>=L (Region III) And its not been too bad. Up until a point. I know for I \psi(x)=0. In...

A tourist being chased by an angry bear is running in a straight line toward his car at a speed of 4.5 m/s. The car is a distance d away. The bear is 24 m behind the tourist and running at 6.0 m/s. The tourist reaches the car safely. What is the maximum possible value for d? In meters. I...

Acceleration -- Rocket 1d Kinematics NASA has developed Deep-Space 1 (DS-1), a spacecraft that is scheduled to rendezvous with the asteroid named 1992 KD (which orbits the sun millions of miles from the earth). The propulsion system of DS-1 works by ejecting high-speed argon ions out the rear...

Starting from rest, a speedboat reaches a speed of 3.4 m/s in 1.8 s. What is the boat's speed after an additional 2.6 s has elapsed, assuming the boat's acceleration remains the same? I have tried finding the velocity for the first 1.8 seconds v = v_0 + a t 3.4 = 0 + a(1.8) 3.4 / 1.8...

Bond is standing on a bridge, 10 m above the road below, and his pursuers are getting too close for comfort. He spots an approaching flatbed truck loaded with mattresses and decides to jump from the bridge onto the truck to make his getaway. He notes that the telephone poles the truck is passing...

A model rocket is launched straight upward with an initial speed of 70.0 m/s. It accelerates with a constant upward acceleration of 1.00 m/s2 until its engines stop at an altitude of 190 m. (a) What is the maximum height reached by the rocket? m I don't know what I am doing wrong...

A person who walks for exercise produces the position-time graph given with this problem. (b) Calculate the average velocity for each segment to verify your answers to part (a). A m/s B m/s C m/s D m/s B is obviously 0 For A I did .20 of an hour is 300 seconds. And 1km =...

Hi all, I'm trying to solve the 1D Schrodinger equation for an arbritary potential, to calculate Franck Condon factors for absorption and emmision spectra. I can do this using iterative techniques (e.g. the Numerov method), but I can't seem to get it to work by discretrizing the hamiltonian...

I think I'm on the right track for this problem, but I'm not entirely sure. Find the solutions to the one-dimensional infinite square well when the potential extends from -a/2 to +a/2 instead of 0 to +a. Is the potential invariant with respect to parity? Are the wave functions? Discuss the...

Could someone please help me in determine the correct formula(s) to answer this problem? A helicopter is ascending vertically with a speed of 2.50 m/s. At a height of 120 m above the Earth, a package is dropped from a window. How much time does it take for the package to reach the ground...

1D Time-Indep Sch Equation Solutions... I'm trying to write a C++ program which displays a 'moveable' graph showing the solution (wavefunctions) to the Schrodinger Equation for a Simple Harmonic Oscillator. I need a little help with the physics of it. The idea is that (using the mouse) the...

Suppose we live in a one dimensional universe (so just a curved/straight line in 2D space). We live inside it so we can travel in one of two directions. Then we might consider the following scenario for how gravity works in this universe. Suppose this 1D universe starts out as a nearly straight...

http://img437.imageshack.us/img437/8104/untitled1wi.jpg in 1 b) i know that the 4 N goes upwards but in questions like 1 d or e, whta do i do then for 1 d 1) -mgsin30 is going down, ok and frictoin is going down, 2) -mgcos30u ok and the 8 N, is it 3) (8cos-30, 8sin-30)? if so, that's...

I have formula for 1D wave equation: (*) u(x, t) = 1/2 [ f(x + ct) + f(x - ct) ] + 1 / (2c) Integral( g(s), wrt s, from x-ct to x+ct ) I am trying to find u(1/2, 3/2) when L = 1, c = 1, f(x) = 0, g(x) = x(1 - x). However, for (*) to work, the initial position f(x) and initial velocity...

Please tell me if I have done this correctly. A ball is thrown upward from the ground with an initial velocity of 10 m/s. Assume all digits are significant. a. How long before the ball reaches its maximum height? t = (0m/s - 10m/s) / -9.80m/s2 t = 1.0s b. What is the ball's maximum...

Hi all, I am more into physics than maths and I need you guys to please help me out. Also I am new to programming in MATLAB. I have done some but still I consider myself a novice. I need to solve the problem in MATLAB. So here is the problem.Its a 2 point BVP(boundary value problem) along...

A motorist is traveling at 10 meters a second when he sees a deer in the road 50m ahead. If the maximum negative acceleration of his vehicle is -7 meters per second per second, then what is the maximum reaction time delta t of the motorist that will allow him to avoid hitting the deer? I am...

I got the following PDE: Laplasian[F]+a*d(F)/d(teta)=E*F I worked with cylindrical coordinates (r,teta,z) (teta is the angle between the x-axis and the r vector (in xy plane)) a,E are constants I got the constrains: z=0 r=a , so the whole problem is on a simple ring How can I make...

I am doing research with a professor and he asked me to graph some solutions to a 1D diffusion equations of the following form: C_e \frac{\partial T_e}{\partial t}=\frac{\partial}{\partial z}\left( \kappa \frac{\partial T_e}{\partial z} \right) - g(T_e-T_i)+\alpha (1-R)If(t)\exp (-\alpha z)...

I know that psi is equal to (2/a)^1/2 sin(n pi x/a)? what is psi*?

here is the problem.. i keep getting yes for the first part and then around 163 for the second part. please help. Speedy Sue, driving at 31.5 m/s, enters a one-lane tunnel. She then observes a slow-moving van 105 m ahead traveling in the same direction as her at 5.10 m/s. Sue applies her...

A startled armadillo leaps upwards so that it rises to .56 m in a time .21 s. Note: I use a web-submitting thing for my answers. So it tells me what is right and wrong. A: What was the armadillo's initial speed when it left the ground? 3.70 m/s - this part is correct. B: What is its...

47. A rock is dropped from a sea cliff and the sound of it striking the ocean is heard 3.4s later. If the speed of sound is 340 m/s, how high is the cliff? Could somebody map this one out for me, it isn't making any sense.

The question goes as follows: A truck covers 40.0 m in 8.50 s while smoothly slowing down to final speed +2.40 m/s. Find the original speed Find the acceleration Now, I tried a couple things for the speed, I tried 40/8.50, and I tried (4.71/2.40) and both turned out to be wrong. Not...

Problem 1 Ball A is dropped from the top of a building of height H at the same instant ball B is thrown vertically upward from the ground. First consider the situation where the balls are moving in opposite directions when the collide. If the speed of ball A is m times the speed of ball B...

I have a wave equation Ytt=c^2 Yxx - g where g is a constant. The boundary conditions are Y(0,t)=Y(L,t)=0 with initial conditions Y(x,0)=0 and Yt(x,0)=0 I tried to solve it by Laplace transfoming the PDE in time and everything worked fine until I got to the point where I had to inverse the...