Optics Question 422
Question: In a laboratory four convex lenses $ L _{1},L _{2},L _{3} $ and $ L _{4} $ of focal lengths 2, 4, 6 and 8 cm respectively are available. Two of these lenses form a telescope of length 10 cm and magnifying power 4. The objective and eye lenses are
[MP PMT 2001]
Options:
A) $ L _{2},L _{3} $
B) $ L _{1},L _{4} $
C) $ L _{3},L _{2} $
D) $ L _{4},L _{1} $
Show Answer
Answer:
Correct Answer: D
Solution:
To make telescope of higher magnifying power, $ f _{o} $ should be large and $ f _{e} $ should be least.
