Question

Orders of magnitude 4: Assume again a Rubidium atom (mass m=87⋅u) is initially at rest. Again it then absorbs a photon of wavelength λ=780 nm. What is the kinetic energy Ekin of the atom after this process? Please give the energy in μK⋅kB units. This is an equivalent temperature unit: (Tequiv=E/kB), with the temperature in μK (within 1%).