The bulk modulus of a substance is the ratio of a small decrease in pressure to the resulting fractional increase in volume:

Show that B = (5/3) P, in the free electron gas model, and use your result in Problem 5.21(d) to estimate the bulk modulus of copper. The observed value is 13.4 x 10¹⁰ N/m², but don’t expect perfect agreement—after all, we’re neglecting all electron–nucleus and electron–electron forces! Actually, it is rather surprising that this calculation comes as close as it does.

Problem 5.21(d)

(d) Calculate the degeneracy pressure (Equation 5.57) of copper, in the electron gas model.

Equation 5.57

Transcribed Image Text:

B=-dp AP .