Q. The focal length of lens depends on :
A. The radii of curvature of its surfaces
B. The refractive index of its material
C. The refractive index of the medium surrounding
D. All of the these factors
Answer: All of the these factors
A. The radii of curvature of its surfaces
B. The refractive index of its material
C. The refractive index of the medium surrounding
D. All of the these factors
Answer: All of the these factors