Problem 6.69

A free electron was initially confined within a region with linear dimensions \(l=0.10 \mathrm{nm}\). Using the uncertainty principle, evaluate the time over which the width of the corresponding train of waves becomes \(\eta=10\) times as large.

\Delta t \approx \eta m l^{2} / \hbar \approx 10^{-16} \mathrm{~s}

Wave Properties of particles. Schrodinger Equation.