I have been working out a few problems and something odd struck me:
Sagittal Power = D * [ 1 + (sin^2(theta) / 2n)]
Tangential Power = D * [ (2n + sin^2(theta)) / (2n*cos^2(theta)) ]
Well we could rearrange the tangetial formula to read:
Tangential Power = Sagittal Power / cos^2(theta)
Wouldn't that be a heck of a lot easier to remember?
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