XII Physics Ray Optics Practice Questions PDF

CHAPTER END PRACTICE QUESTIONS STUDENT NAME: ___________________________________ CLASS: _____DATE: _____________ CLASS: XII TOPIC: RAY OPTICS...

CHAPTER END PRACTICE QUESTIONS STUDENT NAME: ___________________________________ CLASS: _____DATE: _____________ CLASS: XII TOPIC: RAY OPTICS MCQ Q.1. Which of the following is not due to total internal reflection? a) Brilliance of diamond b) Working of optical fibre c) Difference between apparent and real depth of a pond d) Mirage on hot summer days Q.2. An object is placed at the focus of the convex mirror. If its focal length is 20cm, the distance of image from the mirror is a) 10cm b) 20cm c) 40cm d) None of the above Q.3. An object is placed at the focus of a concave mirror. If the focal length of the mirror is 20cm, then the distance of image from the pole is a) 10cm b) 20cm c) 40cm d) Infinity Q.4. The relation between angle of incidence i , angle of prism A and angle of minimum deviation 𝑑𝑚 for a triangular prism is Q.5. The critical angle for total internal reflection from a medium to vacuum is 30º. The velocity of light in the medium is a) 3 × 108m/s b) 1.5 × 108m/s c) 6 × 108m/s d) √3 × 108m/s Q.6. A beam of light passes from air to glass. How does the speed of light vary a) decreases b) increases c) remains unchanged d) it may decrease or increase, depending on the colour Q.7. A convex length of focal length is put in contact with a concave lens of same focal length. The equivalent focal length of the combination is a) zero b) f c) 2f d) Infinity Q.8. Half of the lens is wrapped in black paper. How will it change the image a) Size of image is halved b) Intensity of image is halved c) There is no change in the size of image or intensity d) Both size and intensity of the image are changed. Q.9. Which of the following produces virtual as well as real image. a) Concave lens and Convex mirror b) Convex Mirror and Convex lens c) Convex lens and Concave mirror d) Concave mirror and Concave lens Q.10. What is the nature of the graph between 1/𝑢 and 1/𝑣 for a convex lens where u is the distance of the object and v is that of the image? a) Straight line b) Parabola c) Ellipse d) Hyperbola Q.11. A ray of light passes through a plane glass slab of thickness t and refractive index µ = 1.5, The angle between the incident ray and the emergent ray will be a) 0º b) 30º c) 45º d) 60º Q.12. A convex lens of power 4D and a concave lens of power 3D are placed in contact. What is the equivalent power of the combination? a) 7D b) 4/3D c) 1D d) 3/4D Q.13. A lens behaves as a diverging lens in air (n=1) and a converging lens in water (n=1.3). The refractive index µ of the material of the lens is Q.14. For using a convex lens as a magnifying glass, where should we place the object? a) At the principal focus b) Nearer to the lens c) At 𝑓/2, where f = focal length d) Anywhere Q15. A lens of power 3.5D is placed is contact with a lens of power -2.5D. The combination will behave like a) A convergent lens of focal length 100cm b) A divergent lens of focal length 100cm c) A convergent lens of focal length 200cm d) A divergent lens of focal length 200cm Q.16. A convex lens of focal length 10 cm is placed in contact with a concave lens of focal length 20cm. What is the nature and focal length of the combination? a) Concave,10cm b) Convex, 10cm c) Concave, 20cm d) Convex, 20cm Q.17. A convex lens of focal length 16cm forms a virtual image of double the size of the object. What is the distance of the object from the lens? a) 8cm b) 16cm c) 24cm d) 32cm Q.18. The angle of prism is 30º and ray incident at 60º on one refracting surface suffers a deviation of 30 º. What is the angle of emergence? a) 0 º b) 15 c) 30 º d) 45 º Q.19. A ray of light passes through an equilateral prism such that the angle of incidence is equal to angle of emergence and the later is equal 3/4th the angle of prism. The angle of deviation is a) 45 º b) 39 º c) 20 º d) 30 º Q.20. A convex length of focal length 15cm is made of material having refractive index 1.2. When placed in water of refractive index 1.3 it will behave as a) Converging lens of focal length 15cm b) Converging lens of focal length different than 15 cm c) Diverging lens of focal length 15cm d) Diverging lens of focal length different than 15 cm Q.21. A student measures the focal length of a convex lens by putting an object pin at a distance 'u' from the lens and measuring the distance 'v' of the image pin. The graph between 'u' and 'v' plotted by the student should look like Q.22. A biconcave lens of power P vertically splits into two identical plano-concave parts. The power of each part will be (a) 2P (b) P/2 (c) P (d) P/√2 Q.23. A prism has refractive angle 60°. When a light ray is incident at 50°, then minimum deviation is obtained. What is the value of minimum deviation? (a) 40° (b) 45° (c) 50° (d) 60 Q.24. A convex lens has focal length f. It is cut in to two equal parts perpendicular to its principal axis. The focal length of each part is a) f/2 b) f c)3/2f d) 2f Q.25. A ray of light travels from vacuum to a medium of refractive index n. If the angle of incidence is found to be twice angle of refraction, then angle of incidence is ________________________ ____________________