Physics-DPP-3-Ray Optics

PHYSICS Topic: RAY OPTICS Date: 1. A spherical surface of radius of curvature R separates air (refractive index 1.0) from glass (refractive index 1.5). The centre of curvature is in the glass. A point object P placed in air is found to have a real image Q in the glass. The line PQ cuts the surface at a point O, and PO = OQ. The distance PO is equal to (a) 2R (b) 3R (c) R (d) 1.5R 2. A beam of light consisting of red, green and blue colours is incident on a right angled prism, fig. The refractive indices of the material of the prism for the above red, green and blue wavelengths are 1.39, 1.44 and 1.47 respectively. The prism will (a) separate part of the red colour from the green and blue colours (b) separate part of the blue colour from the red and green colours (c) separate all the three colours from one another (d) not separate even partially any colour from the other two colours. 3. A beam of white light is incident on glass air interface from glass to air such that green light just suffers total internal reflection. The colors of the light which will come out to air are (a) Violet, Indigo, Blue (b) All colours except green (c) Yellow, Orange, Red (d) White light 4. A ray of light undergoes deviation of 30° when incident on an equilateral prism of refractive index inside the prism with the base of the prism is (a) 30° (b) 45° (c) 60° (d) 0° . The angle made by the ray 5. A ray of light traveling in a transparent medium falls on a surface separating the medium from air at an angle of incidence of 45º. The ray undergoes total internal reflection. If n is the refractive index of the medium with respect to air, select the possible value(s) of n from the following (a) 1.3 (b) 1.4 (c) 1.5 (d) 1.6. 6. A ray of light travels from an optical denser medium to rarer medium. The critical angle for the two media is C. The maximum possible deviation of the refracted light ray can be : (a) π – C (b) 2C (c) π – 2C (d) π – C 2 7. A beam of diameter ‘d’ is incident on a glass hemisphere as shown. If the radius of curvature of the hemisphere is very large in comparison to d, then the diameter of the beam at the base of the hemisphere will be: 3 d 2 (a) 4 d (b) d (c) 3 (d) 3 d PHYSICS Topic: RAY OPTICS Date: 8. One face of a prism with a refracting angle of 30° is coated with silver. A ray incident on other face at an angle of 45° is refracted and reflected from the silvered coated face and retraces its path. The refractive index of the prism is : (a) 2 (b) 3 (c) 3 / 2 (d) 2 9. A ray of light is incident normally on a prism of refractive index 1.5, as shown. The prism is immersed in a liquid of refractive index ' μ '. The largest value of the angle ACB, so that the ray is totally reflected at the face AC, is 30°. Then the value of μ must be : (a) 3 2 5 (b) 3 4 (c) 3 (d) 3 3 4 10. Figure shows a right angle isosceles prism of glass of refractive index 1.414. The angle of incidence i at AB for which the refracted ray through diagonal face goes undeviated is A B C (a) 0° (b) 30° (c) 45° (d) 90°

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