The general formula for destructive interference due to a path difference is given by δ=(m+1/2)λ/n where n is the index of refraction of the medium in which the wave is traveling,...The general formula for destructive interference due to a path difference is given by δ=(m+1/2)λ/n where n is the index of refraction of the medium in which the wave is traveling, λ is the wavelength, δ is the path difference and m=0,1,2,3,… What can you say about the various choices of m in this equation; what physical cases do they represent (assume n=1 for now)?