This quiz works best with JavaScript enabled. Home > Cbse > Class 12 > Science > Physics Part Ii > Class 12 Physics (Part Ii) Chapter 9 Ray Optics And Optical Instruments – Quiz 3 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Physics (Part Ii) Chapter 9 Ray Optics And Optical Instruments Quiz 3 (30 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. What is the angular magnification of a simple microscope when the image is at the near point? A) 1-D/f. B) D/f. C) 1 + D/f. D) D + f. Show Answer Correct Answer: C) 1 + D/f. 2. When light is refracted into a medium, A) Its wavelength and frequency both increase. B) Its wavelength increases but frequency remains unchanged. C) Its wavelength decreases but frequency remains unchanged. D) Its wavelength and frequency both decrease. Show Answer Correct Answer: C) Its wavelength decreases but frequency remains unchanged. 3. A glass concave lens is placed in a liquid in which it behaves like a convergent lens. The refractive index of glass is A) Greater than the refractive index of the liquid. B) Less than the refractive index of the liquid. C) Cannot be decided. D) None of the above. Show Answer Correct Answer: A) Greater than the refractive index of the liquid. 4. A ray of light can suffer total internal reflection when it goes from: A) Water to glass. B) Glass to air. C) Air to glass. D) Air to water. Show Answer Correct Answer: B) Glass to air. 5. How does the magnifying power of a telescope change on increasing the linear diameter of its objective? A) Power remain constant on increases diameter. B) Power doesn't depends on diameter. C) Power decreases on decreases diameter. D) Power increases on increases diameter. Show Answer Correct Answer: D) Power increases on increases diameter. 6. A concave lens has a focal length of-10 cm. If an object is placed 15 cm from the lens, what is the position of the image formed? A) 5 cm on the same side as the object. B) 10 cm on the same side as the object. C) 30 cm on the opposite side. D) 15 cm on the opposite side. Show Answer Correct Answer: A) 5 cm on the same side as the object. 7. What is the effect of temperature on the critical angle? A) Varies randomly. B) Increases with temperature. C) Decreases with temperature. D) Remains constant. Show Answer Correct Answer: B) Increases with temperature. 8. When a beam of light is incident on a plane mirror, it is found that a real image is formed. The incident beam must be A) Converging. B) Diverging. C) Parallel. D) Formation of real image by a plane mirror is impossible. Show Answer Correct Answer: A) Converging. 9. What is the effect of scattering on the color of the sky? A) Red color of the sky. B) Blue color of the sky. C) Yellow color of the sky. D) Green color of the sky. Show Answer Correct Answer: B) Blue color of the sky. 10. An object is placed at a distance of f/2 from a convex lens. The image will be A) At one of the foci, virtual and double its size. B) At 3f/2, real and inverted. C) At 2f, virtual and erect. D) At f, real and inverted. Show Answer Correct Answer: A) At one of the foci, virtual and double its size. 11. Which of the following colour of white light deviated most when passes through a prism? A) Red light. B) Violet light. C) Yellow light. D) Both (i) and (ii). Show Answer Correct Answer: B) Violet light. 12. A convex lens of refractive index 3/2 has a power of 2.5 D in air. If it is placed in a liquid of refractive index 2 then the new power of the lens is A) -1.25 D. B) 1.25 D. C) -1.5 D. D) 1.5 D. Show Answer Correct Answer: A) -1.25 D. 13. An object is placed symmetrically between two plane mirrors, inclined at an angle of 72$^\circ$, then the total number of images observed is A) Infinite. B) 5. C) 4. D) 2. Show Answer Correct Answer: B) 5. 14. What is the relationship between the angles of incidence and refraction at the interface of two media? A) They are independent of each other. B) They follow Snell's law. C) They are inversely proportional. D) They are always equal. Show Answer Correct Answer: B) They follow Snell's law. 15. A tank is filled with water to a height of 12.5cm. The apparent depth of a needle lying at bottom of tank is measured by a microscope to be 9.4cm. What is the refractive index of water? A) 1.5. B) 1.45. C) 1.13. D) 1.33. Show Answer Correct Answer: D) 1.33. 16. The deviation of a ray on passing through a prism is ($\mu$-1)A FOR A) All conditions. B) Small angle A. C) Large angle A. D) In minimum angle of deviation case. Show Answer Correct Answer: D) In minimum angle of deviation case. 17. A person 1.6 m tall is standing at the centre between two walls three metre high. What is the minimum size of a plane mirror fixed on the wall in front of him, if he is to see the full height of the wall behind him? A) 2.3 m. B) 1.5 m. C) 0.8 m. D) 1 m. Show Answer Correct Answer: D) 1 m. 18. In a glass prism: A) Blue light is dispersed more than red light. B) Red light is dispersed more than blue light. C) Both red light and blue light are equally dispersed. D) None of the above. Show Answer Correct Answer: A) Blue light is dispersed more than red light. 19. The angle of minimum deviation for a hollow prism filled with a liquid is 30 degree. A ray of light falling on the prism is refracted at 30 degree. The refractive index of the liquid is: A) 1.414. B) 0.866. C) 1.500. D) 1.732. Show Answer Correct Answer: D) 1.732. 20. Two convex lenses of focal lengths 0.3 m and 0.05 m are used to make a telescope. The distance kept between them is equal to: A) 0.15 m. B) 0.25 m. C) 0.35 m. D) 0.175 m. Show Answer Correct Answer: B) 0.25 m. 21. What is the angle of incidence equal to when light reflects off a smooth surface? A) Angle of dispersion. B) Angle of reflection. C) Angle of refraction. D) Angle of deviation. Show Answer Correct Answer: B) Angle of reflection. 22. What type of image does a convex mirror always form? A) Real and inverted. B) Virtual and erect. C) Both b and c. D) Diminished. Show Answer Correct Answer: C) Both b and c. 23. While measuring refractive index of glass using a glass slab of thickness 3 cm and a travelling microscope a student observes that he needed to shift the microscope by 1 cm to refocus the mark on the base of the travelling microscope when the slab is kept on it. The refractive index of the material of the glass slab is A) 1/3. B) 2/3. C) 1.8. D) 3/2. Show Answer Correct Answer: D) 3/2. 24. What is the power of a lens with a focal length of 50 cm? A) 2 D. B) 0.5 D. C) 3 D. D) 1 D. Show Answer Correct Answer: B) 0.5 D. 25. In a compound microscope, what type of image does the objective lens produce? A) Virtual and erect. B) Virtual and inverted. C) Real and inverted. D) Real and erect. Show Answer Correct Answer: C) Real and inverted. 26. Focal Length of a Lens Combination When lenses are separated by a distance d A) 1/F = 1/f$_{1 }$+ 1/f$_{2 }$-d/f$_{1}$f$_{2}$. B) 1/F = 1/f$_{1 }$+ 1/f$_{2 }$. C) F=f$_{1}$f$_{2}$/f$_{1}$+f$_{2}$. D) None of the above. Show Answer Correct Answer: A) 1/F = 1/f$_{1 }$+ 1/f$_{2 }$-d/f$_{1}$f$_{2}$. 27. Due to refraction, the depth of an optically denser medium appears to be A) Unaffected by refraction. B) Greater than its actual depth. C) Less than its actual depth. D) Equal to its actual depth. Show Answer Correct Answer: C) Less than its actual depth. 28. A short linear object of length b lies along the axis of a concave mirror of focal length f at a distance u from the pole of the mirror. The size of image is approximately equal to A) B ((u-f)/f)1/2. B) B ((f/u)-f)1/2. C) B ((f/u-f)2. D) B ((u-f)/f). Show Answer Correct Answer: A) B ((u-f)/f)1/2. 29. What is the formula for the mirror equation derived in the text? A) 1/v-1/u = 1/f. B) 1/v + 1/u = 1/f. C) 1/v-1/u =-1/f. D) 1/v + 1/u =-1/f. Show Answer Correct Answer: B) 1/v + 1/u = 1/f. 30. The magnifying power of an astronomical telescope in the normal adjustment position is 100. The distance between objective & the eyepiece is 101cm. What is the focal length of objective? A) 100cm. B) 11cm. C) 1cm. D) 50cm. Show Answer Correct Answer: A) 100cm. ← PreviousRelated QuizzesScience QuizzesClass 12 QuizzesClass 12 Physics (Part Ii) Chapter 9 Ray Optics And Optical Instruments Quiz 1Class 12 Physics (Part Ii) Chapter 9 Ray Optics And Optical Instruments Quiz 2Class 12 Physics (Part Ii) Chapter 10 Wave Optics QuizClass 12 Physics (Part Ii) Chapter 11 Dual Nature Of Radiation And Matter QuizClass 12 Physics (Part Ii) Chapter 12 Atoms QuizClass 12 Physics (Part Ii) Chapter 13 Nuclei QuizClass 12 Physics (Part Ii) Chapter 14 Semiconductor Electronics Materials Quiz 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books