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Wave Functions with Uncertainty

The Wave function of a particle is seen in the attachment. a) Assuming that this function is continuous, what can you conclude about the relationship between b and c? b) Draw graphs of the wave function and the probability density over the interval -2mm <= x <= 2mm. c) What is the probability that the particle will be

Transverse Wave Properties

A uniform rope of mass m and length L hangs from a ceiling. (a) Show that the speed of a transverse wave in the rope is a function of y, the distance from the lower end, and is given by v = Sqrt(gy). (b) Show that the time it takes a transverse wave to travel the length of the rope is given by t = 2sqrt(L/g). (Hint: calculat

Mean position in a 1-D harmonic oscillator

Obtain the mean position, <x>, for a particle moving in a 1-D harmonic oscillator potential, when the particle is in the state with normalized wavefunction: Y(x)= ((a/(4*pi))^.25)*(2ax^2-1)*exp((-ax^2)/2)

Commutation relations and the uncertainty principle: normalized wave function

View the attached file for proper formatting of formulas. Consider two hermitian operators A and B which satisfy the following commutation relation: [A, B] = AB-BA=iC, where C is also a hermitian operator in general. Let us introduce a new operator Q defined by: Q=A+ i&#955;B, with &#955; being a real number, and consider

Wave Function: A Linearly Polarized Wave

Please give a step by step solution: 1) The wave function for a linearly polorized wave on a taut string is: y(x,y)=Asin(wt - kx + phi) where A =0.4m, w=3.2s^-1, k=8.1m^-1, phi = 0.49, t is in seconds and x and y are in meters. What is the speed of the wave in m/s? b) What is the vertical displacement of the string

Question about Nodes of a Standing Wave

(See attached file for full problem description) --- Nodes of a Standing Wave (Cosine) Learning Goal: To understand the concept of nodes of a standing wave. The nodes of a standing wave are points where the displacement of the wave is zero at all times. Nodes are important for matching boundary conditions, for example that

Values of the radius

Find the lesser and greater values of the radius where the n = 2, l = 0 radial probability density has its maximum values.

Equation of motion

Find the equation of motion for a particle at x=6.1 for a transverse sine wave with frequency 208 Hz and amplitude .233 meters if the wave propagates in the x directon at 68 m.s, provided the particle at x=0 has equation of motion y=A sin('omega t).

Harmonic wave function

Write an expression for a harmonic wave that has a wavelength of 2.8 m and propagates to the left with a speed of 13.3 m/s. The amplitude of the wave is 0.12 m.

Radial Wave Function

(a) Use this reursion formula, c_j+1 = (2(j+l+1-n)*c_j)/((j+1)(j+2l+2)), to confirm that when l=n-1 the radial wave function takes the form: R_n,n-1 = (N_n)*r^(n-1)*e^(-r/(na)) (b) Calculate <r> and <r^2> for states psi_n,n-1,m.

Probability of Finding Particles

If a hydrogen atom is in the ground state, what is the probaility of finding the electron in a volume of 1.0 pm^3 at a distance of 52.9 pm from the nucleus, in a fixed but arbitrary direction? 1 pm = 10^-12 m

Electron Tunneling

I am given three unnormalized wavefunctions for the system: psi(x) = 100e^x for x<-4 psi(x) = 0.73 cos[(pi)x/40] for-4<x<4 psi(x) = 100e^-x for x>4 I need to determine the probability of the wavefunction vs. x for this system from x=-10 to x=10 so that I can plot it. I have to comment on the probability of fin

Energy quantization

Derive the infinite square well energy quantization law, directly from the DeBroglie relation p=h/l, by fitting an integral number of half DeBroglie wavelengths l/2 into the width a of the well

Entangled states of wavefunctions.

Suppose that a pair of electrons, A and B, were described by the following wave function: (see attached for equations). (I have rewritten this equation as I believe some of you are having problems reading the text.) What property specific to entanglement must the wavefunction describing an entangled state of two particles

Schrodinger Equation for a Harmonic Oscillator

The schroedinger equation for harmonic oscillator can be written: E*psi = [(h^2)/2m][((d^2)*psi)/(dx^2)] + (1/2)kx^(2*psi) Write and formally differentiate each term to get the second derivative with respect to X. Put it all into the equation as shown and you will see that there will be an infinite number of possible solu

Fermions in harmonic potential.

Two identical, non-interacting spin-1/2 fermions are placed in the 1-D harmonic potential V(x) = (1/2)m ω2x2, Where m is the mass of the fermion and ω is its angular frequency. a. Find the energies of the ground and first excited states of this two-fermion system. Express the eigenstates corresponding to these two