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Consider the particle-in-a-box problem in 1D. A particle with mass m is confined to move freely...

Consider the particle-in-a-box problem in 1D. A particle with mass m is confined to move freely between two hard walls situated at x = 0 and x = L. The potential energy function is given as

(a) Describe the boundary conditions that must be satisfied by the wavefunctions ψ(x) (such as energy eigenfunctions).

(b) Solve the Schr¨odinger’s equation and by using the boundary conditions of part (a) find all energy eigenfunctions, ψn(x), and the corresponding energies, En.

(c) What are the allowed values of the quantum number n above? How did you decide on that?

(d) What is the de Broglie wavelength for the ground state?

(e) Sketch a plot of the lowest 3 levels’ wavefunctions (ψn(x) vs x). Don’t forget to mark the positions of the walls on the graphs.

(f) In a transition between the energy levels above, which transition produces the longest wavelength λ for the emitted photon? What is the corresponding wavelength?

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