1. The problem statement, all variables and given/known data Derive from the uncertainty principle a formula for the relative spread of the spectral line that corresponds to the longest wavelength of the Lyman series. 2. Relevant equations uncertainty principle: σxσp≥[itex]\hbar[/itex]/2 planck constant [itex]\hbar[/itex]=h/2pi h=λp Lyman series: 1/λ=RH(1-1/n2) λ=hc/Ei-Ef 3. The attempt at a solution I'm not quite sure how to go about the problem. I have gathered some formulas I believe will help me out. If I substitute some of these formulas in to the uncertainty principle I get σxσp≥(hc/Ei-Ef)p/(4pi) I'm not sure where to go from here. Any help would be greatly appreciated.