Question

Solve this:
Q.3. Two identical glass ( μ g = 3/2) equiconvex lenses of focal length f each are kept in contact. The space between the two lenses is filled with water ( μ W = 4/3). The focal length of the combination is
(1) f 3
(2) f
(3) 4 f 3
(4) 3 f 4

Answer 1

Answer:

and the answer is option four: 3f4