CP Model a hydrogen atom as an electron in a cubical box with side length $L$ . Set the value of $L$ so that the volume of the box equals the volume of a sphere of radius $a=5.29 imes 10^{-11} mathrm{m},$ the Bohr radius. Calculate the energy separation between the ground and first excited levels, and compare the result to this energy separation calculated from the Bohr model.