| S.No. | Questions | Answer |
| 1. | Who firstly demonstrated experimentally the existence of electromagnetic wave? | Hertz |
| 2. | The working of the quartz crystal in the watch is based on which effect? | Piezoelectric Effect |
| 3. | What is the unit of Radioactivity? | Curie |
| 4. | What is the wavelength of visible spectrum? | 390-700 nanometres |
| 5. | One astronomical unit is the average distance between___? | Earth & Sun |
| 6. | Number of basic S.I. units is ___. | Seven (7) |
| 7. | What is the name of the scientist who stated that matter can be converted into energy? | Einstein |
| 8. | The size of atomic nucleus is of the order of___? | 10^-14 m |
| 9. | A temperature at which both the Fahrenheit and the centigrade scales have the same value? | -40° |
| 10. | In the visible spectrum which colour has the shortest wavelength? | Violet |
| 11. | What is the unit of specific resistance? | Ohm-metre |
| 12. | What do we use as a moderator in nuclear reactor? | Graphite |
| 13. | The mirror used in motor vehicles near the driver’s seat is a__? | Convex Mirror |
| 14. | Electron microscope was invented by__? | Robert Koch |
| 15. | The hydraulic brake used in automobiles is a direct application of__? | Pascal’s Law |
| 16. | The filament of an electric bulb is made of which metal? | Tungsten |
| 17. | Camberts Law is related to__? | Interference |
| 18. | Which waves are used in sonography? | Ultrasonic waves |
| 19. | Which instrument is used to measure the power of electric circuit? | Wattmeter |
| 20. | Splitting of Uranium nucleus releases_____ energy. | Nuclear |
| 21. | kilowatt hour is the unit of__? | Energy |
| 22. | A simple device that is used to either break or complete the electric circuit, is called _____? | Switch |
| 23. | Where the value of ‘g’ (acceleration due to gravity) is maximum? | At poles |
| 24. | Good conductors have many loosely bound __? | Electrons |
| 25. | If the body is hollow, then its centre of gravity lies? | outside the material |
| 26. | A man with a dark skin, in comparison with a man with a white skin, experiences__? | Less heat, Less cold |
| 27. | What is the escape velocity for all objects from the earth? | 11.16 km/sec |
| 28. | If the temperature inside a room is increased, the relative humidity will? | Decrease |
| 29. | If a bar magnet is cut length wise into 3 parts, what will the total number of poles be? | 6 |
| 30. | Light travels in a____? | Straight line |
| 31. | What converts the alternating current into direct current? | Rectifier |
| 32. | Einstein got noble prize for____? | Photoelectric Effect |
| 33. | The nucleus of an atom consists of__? | Neutrons and protons |
| 34. | What is the measuring unit of length of light waves? | Angstrom |
| 35. | How much is one barrel of oil approximately equal to? | 159 litres |
| 36. | The sky appears black from the moon because of___? | Lack of Atmosphere |
| 37. | The specific resistance of a wire varies with its___? | Material |
| 38. | Which instrument is used to measure depth of ocean? | Fathometer |
| 39. | The unidirectional property of a PN-junction is useful for its use as which thing? | Rectifier |
| 40. | The strongest force in the nature is ____? | Nuclear Force |
| 41. | Which is the only natural magnet? | Magnetite |
| 42. | We cannot see during a fog, because of ____. | Scattering of light |
| 43. | In which medium sound travels faster? | Solid |
| 44. | A fast wind can turn the blades of a windmill because it possesses__. | Potential Energy |
| 45. | Which of the following material is used for electric wire heater? | Nichrome |
| 46. | Conversion of chemical energy into electrical energy occurs in which thing? | Battery |
| 47. | The direction of a magnetic field within a magnet is___? | From South to north |
| 48. | What remains constant while throwing a ball upward? | Acceleration |
| 49. | What type of lens is a magnifying glass? | Convex lens |
| 50. | Why does a liquid drop tend to assume a spherical shape? | To minimize surface tension |
| 51. | What happens when soda water bottle falls freely? | No bubbles form |
| 52. | Pure water freezes at what temperature? | 32 F |
| 53. | Why are Metals good conductor of heat than insulator? | they contain free electrons |
| 54. | When some detergent is added to water, the surface tension___? | Decreases |
| 55. | The value of which quantity remains same in all system of units? | Specific Gravity |
| 56. | Distance of stars are measured in___? | Light Years |
| 57. | Nature of sound wave is ____? | Longitudinal |
| 58. | Which is used to initiate fissions? | Neutrons |
| 59. | The total internal reflection can occur when light pass from___. | Denser to Rarer medium |
| 60. | Who discovered Diode Bulb? | Sir J. S. Fleming |
| 61. | Radio waves of constant amplitude can be generated with___? | Oscillator |
| 62. | What is the SI unit of luminous intensity? | Candela |
| 63. | What is the name of short duration wave? | Pulse |
| 64. | The absorption of ink by blotting paper involves___? | Capillary Action |
| 65. | Two drops of a liquid are merged to form a single drop. In this process___? | Energy is released |
| 66. | Which is more elastic – Steel or Rubber? | Steel |
| 67. | An atom bomb is based on the principle of___? | Nuclear Fission |
| 68. | Which instrument is used to measure the scattering of light by particles suspended in a liquid? | Nephetometer |
| 69. | The speed of light with the rise in the temperature of the medium ___? | Remains unaltered |
| 70. | Most commercial nuclear power plants worldwide are cooled by __? | Water |
| 71. | Electric Motor converts____? | Electric energy to
mechanical energy |
| 72. | Nuclear sizes are expressed in a unit named____? | Fermi |
| 73. | Weightlessness experienced in a spaceship is due to___? | Absence of Gravity |
| 74. | The blue colour of the clear sky is due to ____? | Dispersion of Light |
| 75. | What does airbag, used for safety of car driver, contain? | Sodium Azide |
| 76. | Radian is used to measure___? | Angle |
| 77. | Who had showed that the electric and magnetic waves are equal in vacuum? | James Clerk Maxwell |
| 78. | When a red glass is heated in dark room it will seem___. | Green |
| 79. | The friction force exerted by fluids is called ___. | Drag |
| 80. | Which is used in designing ships and submarines? | Archimedes Principle |
| 81. | Which instrument is used to measure change in volume of substances? | Dilatometer |
| 82. | On which principle, transformer works? | Mutual Induction |
| 83. | Potential energy of your body is minimum when you ___. | Lie down on ground |
| 84. | The velocity of sound in air___? | 332m/sec |
| 85. | Beats occur because of __? | Interference |
| 86. | In summer, the mirages are seen due to the phenomenon of __? | Total Internal Reflection |
| 87. | Who gave the first experimental value of G? | Cavendish |
| 88. | Astigmatism can be corrected by__? | Cylindrical lenses |
| 89. | What apparatus is used to locate a submerged object? | SONAR |
| 90. | The image formed by convex lens in a simple microscope is__. | Virtual & Erect |
| 91. | What is the unit of magnetic flux? | Maxwell |
| 92. | Coolis tube is used to produce___? | X-Rays |
| 93. | Sudden fall in barometer is indication of___? | Storm |
| 94. | Force of attraction between the molecules of different substances is called___? | Adhesive Force |
| 95. | What is the working principle of Washing machine? | Centrifugation |
| 97. | Insects can move on the surface of water without sinking due to___. | Surface tension of water |
| 98. | The temperature of the sun is measured with ___. | Pyrometer |
| 99. | Acceleration acts always in the direction__? | of the net force |
| 100. | Which instrument is used to measure altitudes in aircrafts? | Altimeter |
Waves » Exercise - 15. What types of waves required material medium ? (a) Sound wave (b) Light wave (c) Current (d) None of these