Box Definition and 1000 Threads

Homework Statement A box rests on top of a flat bed truck. The box has a mass of m = 15.0 kg. The coefficient of static friction between the box and truck is μs = 0.8 and the coefficient of kinetic friction between the box and truck is μk = 0.63. I had previously calculated in an earlier...

Homework Statement A 7-kg box is being lifted by means of a light rope that is threaded through a single, light, frictionless pulley that is attached to the ceiling. If the box is lifted, at constant acceleration, from rest on the floor to a height of 1.5 m above the floor in 0.42 s, what...

Homework Statement A small box of mass is sitting on a board of mass and length L . The board rests on a frictionless horizontal surface. The coefficient of static friction between the board and the box is . The coefficient of kinetic friction between the board and the box is, as usual, less...

While reviewing for my midterm I came across an old problem that asked me to find the expansion coefficient for n=1 given an expression for the superposition wavefunction. I also know the expressions for the individual eigenstates because it is simply considering a particle in a 1-D box. I am...

Homework Statement An electron is confined within a three-dimentional cubic region the size of an atom where L = 200 pm. a) write a wave equation for the electron b) wirte a general wave function for the possbile states of the electorn. List any quantum numbers and their possible values...

Homework Statement A box of mass   4.0 kg is placed at rest on a ramp. The coefficients of static and kinetic friction are $&  0.35 and $%  0.22, respectively. As the ramp is slowly raised from a horizontal orientation, find the critical angle above which the box starts to slide...

Homework Statement Two people pull on a 25kg box that is resting on smooth ice. What is the acceleration of the box? Assume friction is negligible. the img is important bc of the description of the two forces acting on the box. try and ignore my frustrated chicken scratch. t1=50 t2=100...

A box slides down a frictionless plane that makes an angle of 35 degrees with the horizontal. A horizontal force of half the box's weight presses the box against the plane. What is the box's acceleration? I'm confused as to what kind of effect would a horizontal force have on an object...

Homework Statement A 60 kg man stands in a 30 kg box on a light weighing machine. If the box is kept at rest due to force applied by the man by the rope , what is the weight shown by the weighing machine? Homework Equations The Attempt at a Solution .answer given in book is 15...

Homework Statement The object is a box with a given mass m. Our person has the choice between pushing the box with a horizontal force, or pulling the box with a wire with an angle of θ=30o. The magnitude of Fo is the force vector he affects the box with in both cases. Is it possible (If you...

A box contains V balls of which N_{g} are green, N_{r} are red and V-N_{g}-N_{r}=N_{b} are blue. Now somebody shakes the box vigorously, brings it to rest and then observes the arrangement of the balls in the box. Suppose this is repeated many times so that probabilities of different ball...

Homework Statement The object is a box with a given mass m. Our person has the choice between pushing the box with a horizontal force, or pulling the box with a wire with an angle of θ=30o. The magnitude of Fo is the force vector he affects the box with in both cases. Should the box be...

Homework Statement A block with a mass of m is initially moving up the incline and is increasing speed with an acceleration of a. The applied force F is horizontal. The coefficients of friction between between the block and incline are μs=S and μk=K. The angle of the incline is θ. What is the...

Homework Statement Force A 250 degrees @ 200 N Force B 150 degrees @ 300 N Force C 50 degrees @ 400 N mass = 40kg mew = .14 what is acceleration Homework Equations Fa^2 = Fy net^2 x Fx net^2 Fn = Fg Ff = Fn x mew Fnet = Fa - Ff F= ma The Attempt at a Solution Fax=Cos...

Homework Statement The handle of a floor mop makes an angle θ = 28.6o with the horizontal. Assume the handle is massless, and the mop has mass M = 1.4 kg. The coefficient of kinetic friction between the mop and the floor is μk = 0.386. Find F, the magnitude of the force, exerted downward...

Homework Statement The question says to solve the Schrodinger equation for a particle in a box with periodic conditions and then it gives. ψ(0)=ψ(a) The Attempt at a Solution I used the above BC and I also did it as its derivative. (It wasn't stated but I assumed it was implied. I had no...

Homework Statement The question is posted here: http://galileo.phys.virginia.edu/classes/252/mass_and_energy.html I'm not too convinced by their explanation of 'compensation of shift in centre of mass' The Attempt at a Solution What I understand is this: 1)Box of mass M moves distance d...

Homework Statement A box of weight 200N is pushed so that it moves at a steady speed alog a ramp, through a height of 1.5m. The ramp makes an angle of 30° with the ground. The frictional force on the box is 150N while the box is moving. What is the work doe by the person? Homework...

Homework Statement http://img59.imageshack.us/img59/493/capturemml.png The Attempt at a Solution Here is my attempt. I assumed that both the man and the box would slide down the incline. (The box is the left diagram and the man is on the right)...

Homework Statement An electron is confined in a one-dimensional box (an infinite well). Two adjacent allowed energies of the electron are 1.068 × 10-18 J and 1.352 × 10-18 J. What is the length of the box? (h = 6.626 × 10-34 J · s, mass of electron = 9.11 × 10-31 kg) Homework Equations \Delta...

Homework Statement An excited electron (quantum number =4) in a 1D potential box de-excites to the ground state and emit a photon. This photon subsequently becomes absorbed by an electron in a hydrogen atom. The electron in the hydrogen atom becomes excited to an excited state with quantum...

The ground state for two identical fermions in a box (in 1D) is given by: \psi (x_{1},x_{2})_{12} = \frac{\sqrt{2}}{a}[sin(\pi x_{1}/a)sin(2\pi x_{2}/a) - sin(2\pi x_{1}/a)sin(\pi x_{2}/a)] The book I'm reading though says that this state is non degenerate, and that the next excited state...

Homework Statement An open box of maximum volume is to be made from a square piece of material 24 centimeters on a side (24-2x) by cutting equal squares from the corners and turning up the sides. The table shows the volumes V (in cubic centimeters) of the box for various heights, x (in...

A theoretically perfect mirror with no gaps cracks, (no absorbing surfaces), so small that only a single photon could tightly fit inside Is it stopped? If so let's get our scales ;)

Hey everyone. Since it is nearest the end of the summer semester for the Lab component of my classes, Our professor is having do the 'Black Box' project. From the information he gave us, there are three component in a L-configuration, an inductor, capacitor, and a resistor. The Box itself had...

μSomeone is pushing a packing case of mass 30 kg up an inclined slope of angle 11.3deg. as shown in the diagram below. The coefficient of kinetic friction between the case and the slope is µk = 0.100 and the coefficient of static friction is µ = 0.200. 1. The minimum force the person must...

Homework Statement A ball with mass 2.5 kg is moving in outer space with a velocity of 6.0 m/s horizontally, and a box of mass 4.5 kg is moving with a velocity of 4.0 m/s at a angle of 120 degrees from the horizontal. the two collide and stick together. Find the final velocity of the pair...

Homework Statement A horizontal force fo 190N is needed to pull a 70kg box across a horizontal floor at a constant speed. What is the coefficent of friction between the box and the floor? Homework Equations Fnet = ma The Attempt at a Solution My setup is F - F_f = m*a But I...

Hi, a friend and I were talking and a question came up about a delayed force. It goes like this: This is hypothetical obviously. You have the sun and the Earth pulling on each other because of gravity. (The force of the pull between them does not matter, it just has to be equal.) The sun and...

How can I make a box around text in Java which will appear in Windows cmd.exe? Only using System.out.print("X"); and System.out.println("X"); . It MUST be a solid box and not use symbols like - or _ . It can also use int X , double X, char X, String X, and boolean X. Please explain...

Our lab is looking at designing a new ECAP machine (Equal Channel Angular Pressing). It needs to be driven by an electric motor attached to a gearbox. From their modeling and data collected from their existing ECAP machine they are requesting the output shaft on the gearbox to have a 2,000,000...

An evacuated cubical box of side a is constructed with perfectly reflecting interior surfaces; initially, it is dark inside. A small window is opened to allow light of frequency f to enter the container and is also closed again when the box contains N photons. Suggest what might happen if the...

Homework Statement A manufacturer wants to design a box having a square base and a surface area of 108m^2. What dimension will produce a box with maximum volume?Homework Equations a=x^2+4xy V=x^2y a=108m^2 The Attempt at a Solution

Dear Physics Forum, I think I am confused in applying the correspondence principle in QM, using the particle in a box and de Broglie wavelength calculations for massive (macroscopic) objects. Why is the calculated energy of a massive object so small in the particle in a box E = h2/8mL2...

Say I have a cuboid box (eg 120 * 60 * 10cm (lbh)). Is there a way I can add non-uniform mass to it to force the center of gravity on a preferred point (eg making one half heavier than other) - and then when I drop it horizontally or vertically, it always touches the ground at same side (but may...

(a) A box of mass m, attached to a spring, oscillates in simple harmonic motion on a frictionless surface as indicated in the figure below. Each time the box reaches the point of maximum displacement a child allows some sand to fall vertically into the box. This will gradually increase the mass...

Homework Statement A box is hurled up an incline plane of 20 degrees at 10m/second. There is no friction. What is the velocity after 3 seconds. I know gravity and the sin of 20 degrees has to be factored in. Homework Equations v=u+at. u is initial velocity, v is velocity after 3...

Homework Statement The (normalized) wavefunction of the particle is defined as: \psi_n = \sqrt{\frac{2}{L}} \sin \left ({\frac{\pi n}{L} x} \right ) for 0 \leqslant x \leqslant L and \psi_n = 0 otherwise, where L is the length of the one-dimensional box and n is the particle's energy...

I've obtained an insulated plastic cooler box. I want to use this when sea fishing to store my catch and keep it chilled as cold as possible until I can get it home. I intend to load a quantity of ice cubes into the bottom of it and drop the caught fish on top of the ice. My question is - Should...

Homework Statement two identical particles of spin 1/2 that confined in a cubical box of side L. find the energy and wave function (non-interacting between particles) Homework Equations for a cubic boxby and reducing the Schrodinger equation: ψ(x,y,z)=√(8/L3 ) sin((nx πx)/L)sin((ny...

Homework Statement Well, I have this spring (stiffness k and free length l_{0}) mass ( m ) system in a box which has a width w such that l_{0}>w (i.e. the spring is compressed). The box is excited (given a prescribed position) by: u(t)=b\cdot sin({\omega}\cdot t). Determine the range of...

Hello everyone, I am a music composer and total noob. So please excuse my lack of engineering knowledge. I am attempting to build a music box that can play without having to turn the gear's crankshaft manually. Here is a picture of the music box: I have been doing some research and think I...

Hi guys! I thought it was intergrationintegration, i think its differentiation. Im having problems trying to figure out where to start with this question: A rectangular tank with a square base x meters and height h meters is to be made from two different materials. Material for the...

Homework Statement A horizontal spring with spring constant 97.9 N/m is compressed 18.2 cm and used to launch a 2.96 kg box across a frictionless, horizontal surface. After the box travels some distance, the surface becomes rough. The coefficient of kinetic friction of the box on the surface...

Purpose of the "closed box" It's often stated that GR follows from the observation that an experimenter inside a closed box in freefall could not distinguish between the box being in that circumstance, and the box being in open space away from any gravitational field. In each case, objects...

An electron is enclosed in a large rectangular box. Considering gravity, estimate the order of magnitude of the thickness of the layer that is occupied by the electron at the bottom of the box. I thought about this for a long time and I really have no idea how to proceed. Any thoughts?

i have to design one shielding box. in that there is cylinder having high voltage +60kev. and box having metal plate. so i have to calculate the electric field on that cylinder and then decide , what should be the distance in between plate and cylinder. i have attach the geometry on the file...

Given the following sequence in the product space R^ω, such that the coordinates of x_n are 1/n, x1 = {1, 1, 1, ...} x2 = {1/2, 1/2, 1/2, ...} x3 = {1/3, 1/3, 1/3, ...} ... the basis in the box topology can be written as ∏(-1/n, 1/n). However, as n becomes infinitely large, the basis...

Hi, I have a question about the famous Bertrand's box paradox. In this puzzle there are three boxes: a box containing two gold coins, a box with two silver coins, and a box with one of each. After choosing a box at random and withdrawing one coin at random that happens to be a gold coin, the...

Homework Statement The situation is indicated in the diagram below. Block m is at rest, and the block M has an initial velocity upward. Need to find the Lagrangian of this system, and then the Euler-Lagrange equations. The Attempt at a Solution This is the Lagrange that I came up with...