(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Consider a particle confined within a box in the shape of a cube of edges L_{x}=L_{y}=L_{z}.

(a) Suppose that the partice is in a given state specified by particular values of the principal quantum numbers n_{x}, n_{y}, n_{z}. By considering how the energy of this state must change when the length L_{x}of the box is changed quasistatically by a small amount dL_{x}, show that the force exerted by the particle in this state on a wall perpendicular to the x-axis is given by F_{x}=-partial derivative of E with respect to partial derivative of L_{x}

2. Relevant equations

X_{a,r}=-partial derivative of E_{r}wit respect to partial derivative of x_{a}

where X_{a,r}is the generalized force (conjugate to the external parameter x_{a}) in the state r

3. The attempt at a solution

I derived an expression for the quantized energy which is (h^{2}(n_{x}^{2}+n_{y}^{2}+n_{z}^{2})/(8mL_{x}^{2})

Do I have to use pressure to some extent? Any advice would be greatly appreciated

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# Homework Help: Statistical Mechanics and Thermodynamics

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