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Key Equations

# Key Equations

 speed of light, frequency, and wavelength $c=fλc=fλ$ change of wavelength with index of refraction $λn=λnλn=λn$ two-slit constructive interference $dsinθ=mλdsinθ=mλ$, for m = 0, 1, −1, 2, −2, … two-slit destructive interference $dsinθ=(m+½)λdsinθ=(m+½)λ$, for m = 0, 1, −1, 2, −2, … one-slit, first-order destructive interference; wavelength related to dimensions $DyL=λDyL=λ$ one-slit destructive interference $Dsinθ=mλDsinθ=mλ$
 wavelength change with change in medium $λn=λnλn=λn$ diffraction grating constructive interference $dsinθ=mλdsinθ=mλ$ resolution $θ=1.22λDθ=1.22λD$