A thin convex lens L ( refractive index = 1.5  ) is placed on a plane mirror M. When a pin is placed at A , such that OA=18\:cm , its real inverted image is formed at A itself , as shown in figure . When a liquid of refractive index \mu _{l} is put between the lens and the mirror , the pin has to be moved to A' such that OA'=27\:\:cm , to get its inverted real image at A' itself . The value of \mu _{l} will be :

  • Option 1)

    \frac{4}{3}

  • Option 2)

    \frac{3}{2}

  • Option 3)

    \sqrt{3}

  • Option 4)

    \sqrt{2}

 

Answers (1)

P_{initial} = 2P_{L} = \frac{1}{9} \Rightarrow P_{L} = \frac{1}{18}

P_{final}=2P_{L}+2P^{'} = \frac{2}{27}

2P^{'}=\frac{2}{27}-\frac{1}{9} \Rightarrow P^{'}=-\frac{1}{54}

-\frac{1}{54}=(\mu-1)\left ( \frac{1}{-18}-\frac{1}{\infty } \right )

\Rightarrow \mu=\frac{4}{3}

 


Option 1)

\frac{4}{3}

Option 2)

\frac{3}{2}

Option 3)

\sqrt{3}

Option 4)

\sqrt{2}

Most Viewed Questions

Preparation Products

JEE Main Rank Booster 2022

Booster and Kadha Video Lectures, Unlimited Full Mock Test, Adaptive Time Table, 24x7 Doubt Chat Support,.

₹ 6999/- ₹ 799/-
Buy Now
Knockout JEE Main 2022 (One Month)

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Live Classes, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 13999/- ₹ 6999/-
Buy Now
Knockout JEE Main 2023 (One Month)

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Live Classes, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 13999/- ₹ 6999/-
Buy Now
Knockout JEE Main (One Month Subscription)

- AI Coach Study Modules, - Unlimited Mock Tests, - Expert Mentorship, - Study Improvement Plan.

₹ 2999/- ₹ 1999/-
Buy Now
Knockout JEE Main (Twelve Months Subscription)

- AI Coach Study Modules, - Unlimited Mock Tests, - Expert Mentorship, - Study Improvement Plan.

₹ 23999/- ₹ 14999/-
Buy Now
Boost your Preparation for JEE Main 2021 with Personlized Coaching
 
Exams
Articles
Questions