JEE Mains · Physics · STD 12 - Ray optics and optical instruments
- JEE Mains 2021
- Hard
- MCQ
Given below are two statements : one is labelled as Assertion \(A\) and the other is labelled as Reason \(R\). Assertion \(A :\) For a simple microscope, the angular size of the object equals the angular size of the image. Reason \(R\) : Magnification is achieved as the small object can be kept much closer to the eye than \(25\, cm\) and hence it subtends a large angle. In the light of the above statements, choose the most appropriate answer from the options given below:
Pick an option to check your answer.
Answer & Solution
Correct Answer
(C) Both \(A\) and \(R\) are true and \(R\) is the correct explanation of \(A\)
Step-by-step Solution
Detailed explanation
\(\theta^{\prime}=\frac{ h }{ u _{0}} ; \theta^{\prime}\) is same for both object and image
\(m =\frac{\theta^{\prime}}{\theta}=\frac{ D }{\mu_{0}}\)
\(u _{0} < D\)
Hence \(m > 1\)
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