JEE Mains · Physics · STD 12 - Ray optics and optical instruments
- JEE Mains 2021
- Hard
- Numerical
The image of an object placed in air formed by a convex refracting surface is at a distance of \(10\, m\) behind the surface. The image is real and is at \(\frac{2}{3}\) of the distance of the object from the surface . The wavelength of light inside the surface is \(\frac{2}{3}\) times the wavelength in air. The radius of the curved surface is \(\frac{ x }{13}\, m\). the value of \(^{\prime} x^{\prime}\) is ....... .
Pick an option to check your answer.
Answer & Solution
Correct Answer
(A) \(30\)
Step-by-step Solution
Detailed explanation
\(\lambda_{ m }=\frac{\lambda_{ a }}{\mu} \Rightarrow \mu=\frac{3}{2}\)
\(\frac{\mu}{ v }-\frac{1}{ u }=\frac{\mu-1}{ R }\)
\(\frac{3}{2 \times 10}+\frac{1}{15}=\frac{\frac{3}{2}-1}{ R }\)
\(R =\frac{30}{13}\)
\(=30\)
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