Optics One Liner Questions & Answers
| Questions | Answers | |
| 1 | The visible range of solar radiation is – | 400-700 nm |
| 2 | The wavelength extension of visible light is – | Between 390-780 nm |
| 3 | The wavelength of the visible spectrum is in the range – | 3900 Å – 7600 Å |
| 4 | The human eye is most sensitive to visible light of the wavelength – | 5500 Å |
| 5 | The eye is most sensitive to colours between – | Yellow and green |
| 6 | The nature of radiation of light is – | Like both of wave and particle |
| 7 | Light appears to travel in a straight line because – | The wavelength of light is very small |
| 8 | The speed of light in a vacuum is near – | 3 × 108metre/sec |
| 9 | Velocity of light is maximum in – | Vacuum |
| 10 | The speed of light will be minimum while passing through – | Glass |
| 11 | The time taken to reach the Sunlight up to the surface of earth is approximately – | 8.5 minutes |
| 12 | Who has the highest velocity? | Light |
| 13 | What does not change when light travels from one medium to another? | Frequency |
| 14 | When light waves pass from air to glass the variable affected are – | Wavelength and velocity |
| 15 | When a ray of light travels from a denser medium to a rarer medium then – | It speeds up and bends away from the normal |
| 16 | The formation of glittering colours in the thin foam of soap is the result of the following phenomenon – | Total refection and interference |
| 17 | Total internal reflection can take place when light travels from – | Diamond to glass |
| 18 | A cut diamond shines brilliantly due to – | Total internal reflection |
| 19 | What is the reason behind the extraordinary shining of the diamond cuts in a proper way? | Because it has a fixed deviation for |
| 20 | Optical fibre works on the principle of – | Total internal reflection |
| 21 | In fiber-optic communication, the signal travels in the form of – | Lightwave |
| 22 | ‘Endoscope’ used by the doctors for examining the inside of patient’s stomach, works on the principle of – | Total internal refection of light |
| 23 | The reason of the mirage is – | Total internal refection of light |
| 24 | The technique to integrate and mark the image of a three-dimensional object is – | Holography |
| 25 | Generating images on a screen by focusing an electronic beam on phosphorus-coated screen is called – | Roster Scan |
| 26 | ‘Raman effect’ deals with the light rays passing through – | Only fluids |
| 27 | For reproducing sound, a CD (Compact Disc) audio player uses a – | Laser beam |
| 28 | When a CD (compact disc used in audio and video systems) is seen in sunlight, rainbow-like colours is seen. This can be explained on the basis of the phenomenon of – | Reflection and diffraction |
| 29 | Television signals cannot be received beyond a certain distance because – | The surface of the earth is curved |
| 30 | The technique used to transmit audio signals in television broadcasts is – | Frequency Modulation |
| 31 | In the human eye, light rays get transformed into neural impulses at – | Retina |
| 32 | The image formed on Retina is – | Smaller than object but inverted |
| 33 | Which type of image of an object is formed by eye lens of the retina? | Inverted and Real |
| 34 | The principal reason why it is better to have two eyes than one is that – | It enhances distance and depth perception in us. |
| 35 | Direct viewing of sun during total solar eclipse causes irreversible damage to the eyes. The retinal burn is caused by which component of the sun rays? | Ultraviolet light |
| 36 | The colour of the star is an indication of its – | Temperature |
| 37 | Difusion of light in the atmosphere takes place due to – | Dust particles |
| 38 | The colour of light is determined by its – | Wavelength |
| 39 | Which colors have the longest wavelength? | Red |
| 40 | The light with the shortest wavelength is – | Violet |
| 41 | The sun is visible to us a few minutes before the actual sunrise because of – | Refraction of light |
| 42 | The sun and the moon appear elliptical near the horizon because of – | Refraction |
| 43 | Red light is used in traffic signals because – | It has the longest wavelength |
| 44 | Red light signal is used as a danger signal because – | Red light is scattered least |
| 45 | The Sky appears blue due to – | The blue color is scattered most |
| 46 | An astronaut sees the colour of the sky as – | Black |
| 47 | When we see the sky from a plane in high altitude, then it seems – | Black |
| 48 | The sea seems blue due to – |
Refection of sky and scattering of light by the drops of water
|
| 49 | The (Green) Grass appears green to us because – | It refects green colour light to our eyes |
| 50 | In driving a car which type of mirror would you like to use for observing traffic at your back? | Convex mirror |
| 51 | The image formed by an astronomical telescope is – | Virtual and magnified |
| 52 | The number of images of an object placed between two parallel mirrors is – | Infinite |
| 53 | When a mirror is rotated by an angle θ, the reflected ray will rotate by – | 2θ |
| 54 | Light is made of seven colors. What is the method of separating the colors? | The colours can be separated by a prism |
| 55 | The correct order of colours in a rainbow is – | Blue, green, yellow |
| 56 | The terminal color bands of the rainbow are – | Violet and Red |
| 57 | In which direction the rainbow is seen at 12 noon? | It cannot be seen |
| 58 | An air bubble in water will act like a – | Concave lens |
| 59 | The radius of curvature of the plane mirror is – | Infinity |
| 60 | Reading glasses are made from which type of lense? | Convex mirror |
| 61 | A myopic eye can be corrected by using a – | Concave lens |
| 62 | The focus in the eye is done by – | Change in the convexity of the lens |
| 63 | The change of focal length of an eye lens is caused by action of the – | Ciliary muscles |
| 64 | The least distance of distinct vision is (cm.) – | 25 |
| 65 | The power of a lens is measured in – | Dioptre |
| 66 | If the lens power of glass is +2 dioptre, its focal length will be – | 50 cm |
| 67 | The colour of an opaque object is due to the colour it – | Reflects |
| 68 | Colour in a colour television is produced by a combination of three basic colours, they are – | Red, green and blue |
| 69 | When beams of red, blue, and green lights fall on the same spot, the color of the light becomes – | White |
| 70 | The number of colors contained in the sunlight is – | 7 |