Optics Question 644
Question: Two thin lenses whose powers are +2D and -4D respectively combine, then the power of combination is
[AFMC 1998; CPMT 1996; Very Similar to BHU 2004]
Options:
A) - 2D
B) + 2D
C) - 4D
D) + 4D
Show Answer
Answer:
Correct Answer: A
Solution:
$ P=P _{1}+P _{2}=2D-4D=-2D. $