Q: Which one among the following is the correct focal length of a combination of lenses of power 2.5 D and -2.0 D?
(a)+0.5 m
(b)-0.5 m
(c)+2.0 m
(d)-2.0 m
Correct Answer: (c)
The correct answer is (c): +2.0 m. Subject: General Studies | Sub-topic: Miscellaneous