Q. An astronomical refracting telescope will have large angular magnification and high angular resolution, when it has an objective lens of
A) large focal length and large diameter
B) large focal length and small diameter
C) small focal length and large diameter
D) small focal length and small diameter
Explanation
[Solution] Magnification $= f_o/f_e$ needs large $f_o$; resolving power $\propto D$ needs a large diameter. Answer (1).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.