Magnification by eyepiece
m=f+uf
−Ll=fe+(−(f0+fe)fe
⇒Ll=f0fe
m.p.=fef0=lL
In an astronomical telescope in normal adjustment a straight black line of the length L is drawn on inside part of objective lens. The eye-piece…
NEET UG 2015 — Physics Optics
2015mcqhard
In an astronomical telescope in normal adjustment a straight black line of the length L is drawn on inside part of objective lens. The eye-piece forms a real image of this line. The length of this image is l . The magnification of the telescope is:
Official previous-year question
Held on 30 Apr 2015 · Verified 9 Jul 2026.
Options
- A
lL−1
- B
L−lL+l
- C
lL
- D
lL+1
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