question_answer

An equiconvex lens is cut into two halves along (i) XOX¢ and (ii) YOY¢ as shown in the figure.  Let f, f ¢, f ¢¢ be the focal lengths of the complete lens, of each half in case (i), and of each half in case (ii), respectively Choose the correct statement from the following [CBSE PMT 2003]

A)            \[{f}'=2f,\,{f}''=f\]              

B)            \[{f}'=f,\,{f}''=f\]

C)            \[{f}'=2f,\,{f}''=2f\]            

D)            \[{f}'=f,\,{f}''=2f\]

Correct Answer: D

Solution :