Focal length of a convex lens in air is 25 cm. It is cut into two equal halves along its principal axis. What will be the focal length of each half ?

The focal length of a convex lens is 25 cm. What is its power?

The focal length of a convex lens is 20 cm. What is its power?

An equiconvex lens of focal length 15 cm is cut into two equal halves in thickness. What is the focal length of each half ?

An equiconvex lens of focal length 15 cm is cut into two equal halves in thickness. What is the focal length of each half ?

A equiconcave lens of focal length 15 cm is cut into two equal havles along dotted lines as shown in figure. What will be new focal length of each half.

Focal length of an equiconvex lens is 20 cm. If we cut it once perpendicular to principal axis in and then along principal axis. Then, focal length of each part will be: