Optics Question 599
Question: Two thin lenses of focal lengths 20 cm and 25 cm are placed in contact convex. The effective power of the combination is
[CBSE PMT 1990; RPMT 2001]
Options:
A) 45 dioptres
B) 9 dioptres
C) 1/9 dioptre
D) 6 dioptres
Show Answer
Answer:
Correct Answer: B