Consider a particle of mass m confined to a one-dimensional box of length L and in...

Consider a particle of mass m confined to a one-dimensional box of length L and in a state with normalized wavefunction. For a partide in a box the energy is given by

E_n = n²h²/8mL² and, because the potential energy is zero, all of this energy is kinetic. Use this observation and, without evaluating any integrals, explain why < p_x²>= n²h²/4L²

Expert Solution

The detail explaination of the expression of average momentum is shown below. Since the box is one dimensional thus we assume that the particle moves along X -axis only. Inside the box the potential energy is zero and the all energy inside the box is assumed to be kinetic.

queen_honey_blossom answered 2 years ago

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