[Catherine S.P]

The question requires you to calculate the allowed momenta using the de Broglie wavelength, and then using this calulate the allowed energies in terms of the quantum number n.

Ive got all the equations but Im stuck because the question hasnt given me any numerical values to actually plug into the equations, is there something Im missing for instance assumptions?
All Im given is that it is in a box from O to L and the boundries are to infinity, the potential energy is zero apart from at the wall (ie. when x=0 and x=L) so all energy is kinetic energy....In a book Im using it suggests that the wavefunction of these conditions is psi(x)=CsinkL, do I use this?
If so where did this equation come from?

Thanks in advance

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