If the angle of incidence is small enough, the small angle
Chapter , Problem 22(choose chapter or problem)
If the angle of incidence is small enough, the small angle approximation may be used to simplify Snells law of refraction. Determine the maximum value of the angle that would make the value for the angle differ by no more than one percent from the value for the sine of the angle. (This approximation will be used in connection with image formation by spherical surfaces in Chapter 32.)
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