COMEDK · Physics · 25. Ray Optics
The distance between the objective and eye piece of astronomical telescope in normal adjustment is 27 cm and its magnifying power is 8. What is the focal length of the objective lens?
- A 6 cm
- B 24 cm
- C 12 cm
- D 3 cm
Answer & Solution
Correct Answer
(B) 24 cm
Step-by-step Solution
Detailed explanation
In normal adjustment of an astronomical telescope, the final image is formed at infinity. The length of the telescope tube is the distance between the objective lens and the eyepiece. \(L = f_o + f_e\) The magnifying power of the telescope in normal adjustment is given by:…
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