+91-8076753736 [email protected]

-->

Ray Optics And Optical Instruments

Question

Wired Faculty App

Light wave enters from medium 1 to medium 2. Its velocity in 2^nd medium is double from 1. For total internal reflection the angle of incidence must be greater than

30^o

60^o

45^o

90^o

Solution

A.

30^o

Total internal reflection occurs when the angle of incidence is greater than critical angle

(C) in the denser medium.

Given:- Velocity of light wave in medium '2' is doubled than medium '1'.

${}^{1}μ_{2}$ = $\frac{velocity of light in medium' 1'}{velocity of light in mediun' 2'}$

${}^{1}μ_{2}$ = $\frac{ν}{2 ν}$

${}^{1}μ_{2}$ = $\frac{1}{2}$

Hence medium '1' is denser

⇒ sinC = $\frac{1}{2}$ = 30^o

⇒ C = 30^o

Some More Questions From Ray Optics and Optical Instruments Chapter

Draw a ray diagram to show image formation when the concave mirror produces a real, inverted and magnified image of the object.

Explain two advantages of a reflecting telescope over a refracting telescope.

In an optics experiment, with the position of the object fixed, a student varies the position of a convex lens and for each position, the screen is adjusted to get a clear image of the object. A graph between the object distance u and the image distance v, from the lens, is plotted using the same scale for the two axes. A straight line passing through the origin and making an angle of 45^o with the x-axis meets the experimental curve at P. The coordinates of P will be

An experiment is performed to find the refractive index of glass using a travelling microscope. In this experiment distance are measured by

Two lenses of power -15D and +5D are in contact with each other. The focal length of the combination is

The angle of incidence at which reflected light totally polarized for reflection from air to glass (refractive index n), is

Mock Test Series

Mock Test Series

NCERT Sample Papers

Entrance Exams Preparation