CH-10 Optical Instruments Leave a Comment / By abdulslambsn@gmail.com / October 6, 2025 Welcome To Your Quiz "CH-10 Optical Instruments" Click on "Start Quiz" To Continue... 1. Any transparent medium bounded by one or two spherical surface ,is called: Lens Mirror Prism None of these None 2. A lens which is thicker from middle and thinner from edges called: Convex lens Concave lens Convex mirror Concave Mirror None 3. The ratio of the size of image to the size of object is called: Magnification Angular magnification Classification None of these None 4. The ratio of the angle subtended by the image as seen through the optical device to that angle subtended by the object at the eye is called: Linear magnification Angular magnification Tabulation Calculation None 5. A point where the incident rays of light converge or appears to diverge after passing through the lens is called: Aperture Focus Optical center Pole of lens None 6. The distance of near point from the eye is about: 25 cm 25 m 10 cm 10 m None 7. The distance between the principal focus and the optical centre of the lens is called: Aperture Focal length Radius of curvature None of these None 8. When an object is brought from a far point to the focal point of convex lens, the size of image is: Unchanged Decreasing Increasing All of Above None 9. The apparent size of the object depends upon its actual size and angle subtended by it at the: Eye Face Mouth Near point at eye None 10. The unit of power of lens is: Newton Watt Dioptre None of above None 11. The focal length of convex lens is: Positive Negative Positive and negative None of these None 12. If an object is placed in front of convex lens then the image will be: Real and erect Real and inverted Virtual and erect Virtual None 13. If an object is placed at 2F from convex, lens the image is located behind the lens: Between lens and focus At 2 F Between F and 2 F At the focus None 14. Magnification of a lens is positive when the image is: Real and inverted Virtual and inverted Real and erect None of these None 15. The magnifying power of a simple microscope is: M = 1+f/d M =1+d/f M = 1=fd None of these None 16. The convex lens used in compound microscope as objective has focal length: Large Short Same as eye-piece None of these None 17. If a single convex lens is placed close to the eye then it can be used as: Simple microscope Compound microscope Spectrometer Telescope None 18. The magnifying power of a compound microscope is: Magnification of objective magnification of eye-piece Magnification of objective + Magnification of eye-piece Magnification of object x Magnification of eye-piece Magnification of object - Magnification of eye-piece None 19. The eye-piece of a compound microscope acts as: Converging mirror Converging lens Diverging mirror Diverging lens None 20. If focal length of objective is increased: Magnifying power of compound microscope decreased Magnifying power of astronomical telescope increases Length of astronomical telescope increases All of above None 21. A simple astronomical telescope consists of: Two convex lens Two concave lens One convex and one concave None of these None 22. The image of a distant object viewed through telescope appears: Larger Brighter Smaller Dull None 23. The distance between the objective and eye- piece of a telescope in normal adjustment is: f₀ - fₑ f₀ + fₑ fₑ - f₀ None of these None 24. The magnifying power of an instrument is expressed in: Radians Degrees No units None of these None 25. Lenses of focal lengths 100 cm and 5 cm are used as objective and eye-piece of an astronomical telescope, its length for normal adjustment is: 95 cm 105 cm 20 cm None of these None 26. An optical instrument used to study the properties of light: Spectrometer Simple microscope Telescope None of these None 27. The component of the spectrometer which consists of a fixed metallic tube with a convex lens at one end and adjustable slit is called: Telescope Collimator Turntable Grating None 28. The scientist who correctly measured the speed of light was: Einstein Michelson Gallileo Newton None 29. The speed of light in vacuum or in air is: 3 x 10¹⁰ m/s 3 x 10⁷ m/s 3 x 10⁹ m/s 3 x 10⁸ m/s None 30. Alexander Bell invented advice known as: Photo phone Telescope Spectrometer Microscope None 31. For glass air boundary, the value of critical angle is: 41⁰ 41.5⁰ 41.8⁰ 41.2⁰ None 32. In Michelson's experiment, the equation used to find the speed of light is: c = 16 fd c = 16 f/d c =16 d/f c= fd/16 None 33. The focal length "f" and radius of curvature are related by: f = 2R R = 2f R = f None of the above None 34. In compound microscope the magnification of object is M₀ and magnification of eyepiece is Mₑ. The magnifying power of compound microscope is: M₀ + Mₑ M₀ x Mₑ Mₑ - Mₑ M₀ / Mₑ None 35. In vacuum light travels at a speed of 3 x 10⁸ ms⁻¹, what is the speed of light in glass of refractive index 1.5? 1.5 x 10⁸ ms⁻¹ 2 x 10⁸ ms⁻¹ 3 x 10⁸ ms⁻¹ 4.5 x 10⁸ ms⁻¹ None 36. An object is placed between two parallel mirrors. The number of image formed is: 2 4 8 Infinite None 37. What will be the colour of the sky as seen from the Earth if there were no atmosphere? Black Blue Orange Red None 38. An object of 2 cm tall is placed 15 cm from concave mirror of focal length 10 cm. How far is the image from the mirror? 10 cm - 20 cm -30 cm -40 cm None 39. An observer moves towards a stationary plane mirror at a speed of 4 ms⁻¹, with what speed will what speed will his image move towards him? 2 ms⁻¹ 4 ms⁻¹ 8 ms⁻¹ image will stay at rest None 40. A spectrometer is used to measure: refractive index of material of glass prism Deviation of light by a glass prism Wavelength of light All of above None 1 out of 8 Thanks For Taking This Quiz - Please See Your Answers/Results Below After Entering Your Name & Email... Name Email Time's up
