Practicing Success

Target Exam

CUET

Subject

Physics

Chapter

Ray Optics

Question:

Options:

a

b

c

d

Correct Answer:

c

Explanation:

$\text{Let radius of two surfaces are R and 2R respectively}$

$ \frac{1}{F} = (\mu -1) (\frac{1}{R_1} - \frac{1}{R_2}) = (1.5 -1) (\frac{1}{R} - \frac{1}{-2R}) = \frac{3}{4R}$

$\Rightarrow F = \frac{4R}{3}$

$\Rightarrow R = \frac{3F}{4} = 4.5 cm$

$\text{larger radius of curvature is } 2R = 9cm$