Q5 of 26 Page 1

The focal length of an equiconvex lens is equal to the radius of curvature of either face. What is the refractive index of the material of the lens?

Focal length of a lens is given by:


since r1 and r2 are equal, and focal length f is equal to radius of curvature, i.e. f = r1 = r2, putting these values in above formula. The refractive index μ= 1.5


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