Consider the 1D infinite square-well potential shown in the figure below.
(a) State the time-independent Schrödinger equation within the region 0 < x < L for a particle with positive energy E.
(b) The wavefunction for 0 < x < L can be written in the general form
ψ(x) = A sin kx + B cos kx.
Find the normalised wavefunction for the 1D infinite potential well.
(c) Determine the expectation values of x, p and p² of a particle in the first excited state of an infinite square-well potential.
(d) Sketch the wavefunction, probability densities and energy levels of the first three levels of the infinite square well potential and discuss in relation to your answers in part (c).