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A plano-convex lens has a radius of curvature of the curved surface equal to 30   cm and a refractive index equal to 1 . 5 , then what is the focal length (in cm ) of the lens?

Correct answer

60.00

Step-by-step solution

1 f = ( μ - 1 ) 1 R 1 - 1 R 2 R 1 = ∝ R 2 = - 30 cm 1 f = ( 1 . 5 - 1 ) 1 ∞ - 1 - 30 1 f = 0 . 5 30 f = 60 cm

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