Total Internal Reflection

IMPORTANT

Total Internal Reflection: Overview

This topic covers concepts, such as Total Internal Reflection, Critical Angle, Total Reflecting Prisms, Total Internal Reflection in Liquids, Total Internal Reflection in Diamond, Total Internal Reflection in Mirage, etc.

Important Questions on Total Internal Reflection

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A beam of light consisting of red, green and blue and is incident on a right angled prism. The refractive index of the material of the prism for the above red, green and blue wavelength are 1.39, 1.44 and 1.47 respectively. The prism will

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A ray of light traveling in a denser medium strikes the boundary of a rarer medium and gets partially reflected and refracted. The angle of reflection is r and that of refraction is r'. If the reflected and refracted rays make an angle of 90° with each other, then the critical angle for the pair of media is

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Two glass blocks of triangular cross section(n=1.5) are used to make a periscope. Which of the following is the correct arrangement?

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A point source of light is placed at a distance h below the surface of a large deep lake. What is the percentage of light energy that escapes directly from the water surface is μ of the water = 4/3? (neglect partial reflection)

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A small source of light is 4 m below the surface of a liquid of refractive index 5/3. In order to cut off all the light coming out of liquid surface, minimum diameter of the disc placed on the surface of liquid is

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In the figure ABC is the cross section of a right angled prism and BCDE is the cross section of a glass slab. the value of θ so that light incident normally on the face AB does not cross the face BC is (given sin-1 (3/5) = 37o)

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A rod made of glass (μ=1.5) and of the square cross-section is bent into the shape shown in the figure. A parallel beam of light falls perpendicularly on the plane flat surface A. Referring to the diagram, d is the width of a side & R is the radius of the inner semicircle. Find the maximum value of ratio dR so that, all light entering the glass through surface A emerge from the glass through surface B

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A room contains air in which the speed of sound is 340 m s-1. The walls of the room are made of concrete in which the speed of sound is 1700 m s-1. (a) Find the critical angle for total internal reflection of sound at the concrete - air boundary. (b) In which medium must the sound be travelling to undergo total internal reflection?

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A ray of light from a denser medium strikes a rarer medium at an angle of incidence i (see figure). The reflected and refracted rays make an angle of 90° with each other. The angles of reflection and refraction are  r and r'  The critical angle is

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A glass prism of refractive index 1.5 is immersed in water (refractive index 43). A light beam incident normally on the face AB is totally reflected to reach on the face BC if

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What is looming?

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“Looming” in the polar region-

Complete the statement.

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Looming in optics can be defined as a deceptive appearance of a distant object caused due to bending of light rays in layers of air with varying density.

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Critical angle of light passing from glass to air is minimum for:

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It is possible to observe total internal reflection,when a ray travels from :

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Total internal reflection takes place when the light ray travels from

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The refractive index of glass with respect to air is 2. Then the critical angle of glass-air interface is

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Which one has the highest value of critical angle?

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What is looming in optics?

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A ray of light travelling in a transparent medium of refractive index µ, falls on a surface separating the medium from air at an angle of incidence of 45°. For which of the following value of µ the ray can not undergo total internal reflection ?