Practicing Success

Target Exam

CUET

Subject

Physics

Chapter

Ray Optics

Question:

In the figure given below, APB is a curved surface of radius of curvature 10 cm separating air and a transparent material (µ = 4/3). A point object O is placed in air on the principal axis of the surface 20 cm from P. The distance of the image of O from P will be _________.

Fill in the blank with the correct answer from the options given below.

Options:

16 cm left of P in air

16 cm right of P in water

20 cm right of P in water

20 cm left of P in air

Correct Answer:

16 cm left of P in air

Explanation:

$ \frac{\mu_2}{v} - \frac{\mu_1}{u} = \frac{(\mu_2 - \mu_1)}{R}$

$ \frac{4}{3v} - \frac{1}{-20} = \frac{4/3 - 1)}{-10} \Rightarrow \frac{4}{3v} = \frac{-1}{30} - \frac{1}{20} = \frac{-5}{60} =\frac{-1}{12}$

$ v = -16cm$ , negative sign shows image lies left of the point p

The correct answer is Option (1) → 16 cm left of P in air