Question
Question: The magnifying power of an astronomical telescope is 8 and the distance between the two lenses is 54...
The magnifying power of an astronomical telescope is 8 and the distance between the two lenses is 54 cm. The focal length of eye lens and objective lens will be respectively –
A
6 cm and 48 cm
B
48 cm and 6 cm
C
8 cm and 64 cm
D
64 cm and 8 cm
Answer
48 cm and 6 cm
Explanation
Solution
M = – 8 = – Ž fo = 8fe, L = fo + fe = 54
fe = 6 cm, fo = 48 cm