Question

The refractive index of the material of a double equiconvex lens is 1:5. If the radius of curvature of the lens is r, then its focal length is

Answer 1

Answer:

The radius of curvature is =5 cm. Explanation: The refractive index is. n=1.5 . The focal length is. f=5cm ... r=r1=−r2. Apply the thin lens approximation ... 15=(1.5−1)⋅2r.