Question

what is 2F1,F1,F2,2F2 stands for???

Answer 1

left side of lens

F1=FOCAS

2F1=CENTRE OF CURVATURE

 

 

RIGHT SIDE OF LENS

F2=FOCUS

2F2=CENTRE OF CURVATURE

Answer 2

Answer:

F1 and F2 are the focus of the lens. Why F1 and F2 you may ask.. It is because that a lens have 2 foci.

2F1 and 2F2 are the centre of curvatures, i.e the center of the sphere. The lens have 2 center of curvatures because the lens are bound to have 2 spheres.

Hope this helped!!

FYI: F1 and 2F1 are on the left side and F2 and 2F2 are on the right side of a lens