Question

Assume that an electron is located somewhere within a region of atomic size. Estimate the minimum uncertainty in its momentum by assuming that this uncertainty is comparable with its average momentum. Estimate the average kinetic energy of the electron.

Answer 1

sigma_x*sigma_p >=h/2

sigma
x=10^-8

sigma p=p=3*10^-19

E= p^2/ (2m) = 9*10^(-38)/(2*9*10^-34) = 0.5*10^-4