Four lenses of focal length +15 cm, +20 cm, +150 cm and +250 cm are available for making an astronomical telescope. To produce the largest magnification, the focal length of the eye-piece should be
A) +15 cm
B) +20 cm
C) +150 cm
D) +250 cm
Correct Answer:
A
Solution :
For largest magnification focal length of eye lens should be least.