Optics Question 412
Question: An astronomical telescope of ten-fold angular magnification has a length of 44 cm. The focal length of the objective is
[CBSE PMT 1997]
Options:
A) 4 cm
B) 40 cm
C) 44 cm
D) 440 cm
Show Answer
Answer:
Correct Answer: B
Solution:
$ L=f _{o}+f _{e}=44 $ and $ |m|\ =\frac{f _{o}}{f _{e}}=10 $ .
This gives $ f _{o}=40\ cm $