How does increase in curvature of convex lens leads to decrease in its focal lenght? Please explain with suitable diagram..
Asked by jgprmr | 17th Jun, 2017, 12:07: AM
1) Curvature of a lens means the amount of bend in its refracting surface. So, more the curvature, larger the bend.
2) Now, if a lens is bent to a larger extent, it means it is highly curved and therefore its radius of curvature is low.
3) Imagine this in the form of a circle. If a circle is bent more means it is a smaller circle. Which ultimately means that its radius of curvature is less.
4) Small radius means small focal length. So, the lens focusses light more and more closer to its surface.
5) Hence, an increase in curvature leads to decrease in focal length.
Answered by Romal Bhansali | 17th Jun, 2017, 01:08: PM
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