JEE Mains · Physics · STD 12 - 9. Ray optics and optical instruments
A telescope has an objective lens of focal length \(150\,\,cm\) and an eyepiece of focal length \(5 \,\,cm.\) If a \(50\,\,m\) tall tower at a distance of \(1\,\,km\) is observed through this telescope in normal setting, the angle formed by the image of the tower is \(\theta \), then \(\theta \) is close to.....\(^o\)
- A \(30\)
- B \(15\)
- C \(60\)
- D \(1\)
Answer & Solution
Correct Answer
(A) \(30\)
Step-by-step Solution
Detailed explanation
Magnifying power of telescope, \(M P=\frac{\tan \beta( \text { angle subtended by image at eye piece) } }{\tan \alpha \text { (angle subtended by object on objective) }}\) Also, \(M P =\frac{f_{o}}{f_{e}}=\frac{150}{5}=30\)…
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