GENERAL SCIENCE PRACTICE QUESTIONS

1. The memory of a computer is usually measured in ––
A. Bits B. Bytes C. RAM D. PROM
2. Which of the following requirements must be strictly satisfied by a system in thermo dynamical equilibrium?
A. Mechanical equilibrium B. Thermal equilibrium
C. Chemical equilibrium D. All of the above
3. The force of attraction between earth and an apple is——
A. Gravity B. Electrostatic Force C. Elastic force D. None
4. A body falling freely under the action of gravity has
A. No weight B. Minimum weight C. Maximum weight
D. No effect on its weight
5. Who among the following discovered law of photo electric effect, general theory of relativity etc.
A. Hertz B. Einstein C. Fredrich D. Knipping
6. Which of the following metals show photo-electric effect with ultra-violet light ?
A. Lithium, Sodium, potassium B. potassium, cesium, zinc
C. Zinc, cadmium, magnesium D. magnesium, sodium, cesium
7. Semiconductor meterials are –––––
A. those which do not conduct electricity B. those which conduct electricity partially
C. those which conduct electricity wholly D. All of the above
8. A person can swim comfortably in water. This is due to –––––––
A. Pascal’s law B. Archimede’s principle
C. Newton’s third law D. None of the above
9. Which of the following element when added to a pure germanium crystal forms n-type extrinsic semi-conductor
A. Gallium B. Aluminium C. Antimony D. Indium
10. The method of Radio-carbon dating is used to find the age of –––––
A. fossils B. stars C. Skeletons D. Trees

11. One gm. Wt is equal to
A. 9.8 ergs B. 9.8 dynes C. 980 ergs D. 980 dynes
12. The unit of energy is
A. Watt B. Pound C. Joule D. Newtons
13. Longitudinal waves do not exhibit
A. polarisation B. diffraction C. interference D. dispersion
14. What is the source of electrical energy in an artificial satellite ?
A. Thermopile B. Solarcell C. Mini nuclear reactorD. Dynamo
15. Sound waves cannot travel in
A. solid B. hydrogen C. Oil D. Vacuum
16. Inertia is the property of
A. mass B. volume C. strength D. all the above
17. Movement of a body in a circular path is due to
A. centrifugal forceB. centripetal force C. Artificial force D. Linear force
18. The theory behind the lever and pulleys was first demonstrated by
A. Archimedes B. Newton C. Albert Einstein D. Foucault
19. Example for non-renewable sources of energy is–––
A. Hydrogen B. Petrol C. Geo thermal energy D. Biomass
20. When a cycle is driven on an oily road, it slips because on such roads
A. Friction between tyres and road decreases
B. Friction between tyres and road increases
C. Inertia of tyres increases D. None of the above.
21. Rainbow is caused due to
A. Reflection of sun’s rays from water drops
B. Dispersion of sun’s rays from water drops
C. Total internal reflection from sun’s rays D. None of these
22. Finger prints on a piece of paper may be defected by sprinkling fluorescent powder on the paper and then looking at it in
A. sunlight B. infrared light C. Ultraviolet light D. None of these
23. If train is traveling with the velocity of light, its length would be
A. Infinite B. Zero C. very small or very large
D. None of the above
24. A needle or a pin floats on the surface of water because of
A. surface tension B. viscosity C.. higher weight D. capillarity
25. Light emitted from the sun takes approximately —— to reach the earth
A. 50 seconds B. 10 seconds C. 500 seconds D. 1000 seconds
26. When a man circles round the earth in a satellite, his
A. mass becomes zero but weight remains the same
B. mass remains constant by weight becomes zero
C. mass and weight remains constant D. both mass and weight becomes zero
27. The Milky way ——
A. is stationary B. is not stationary C. revolves sometimes D. never revolves
28. ‘Lyra’, ‘Vega’ and ‘Orion’ are the names of
A. Galaries B. Cosmic rays C. Constellations D. None of these
29. Persistence of vision is the principles behind
A. periscope B. spectroscope C. cinema D. camera
30. In what type of trays will ice cubes be formed more quickly in a freezer ?
A. Wooden trays B. Plastic trays C. Rubber trays D. Aluminium trays
31. In the walking of man ——— is involved
A. Newton’s Ist law B. Newton’s IInd law
C. Newton’s IIIrd law D. None of the above
32. Gravitational forces are
A. The weakest force in nature B. The strongest force in nature
C. Ineffective in nature D. None of the above
33. If a person sitting in a boat in a river throws a large stone with a large velocity, the boat will
A. Move in forward direction B. Move in backward direction
C. Remain stationary D. Oscillate in its position
34. Sound energy is converted into electrical energy by the
A. microphone B. Loud speaker C. telephone D. Ear phone
35. In gases an ultrasonic wave is
A. longitudinal only B. both (A) & (C) C. transverse only D. Neither (A) or (C)
36. “Hydro power” is the term used for electricity produced through
A. Atomic power B. Water C. Mineral oil D. Coal
37. —— was the first to realize that the moon is a satellite of the earth
A. Kepler B. Newton C. Einstein D. Galileo
38. The force due to a magnet is
A. Variable force B. Same at different points
C. Electric in nature D. None of the above
39. A person pushing against a wall
A. Does work B. Does no work unless wall in moved C. produces displacement
D. is wasting his time
40. Why does the human body perspire in summer ?
A. To maintain a constant normal body temperature B. To relax
C. To get more energy D. To intake more cool air.
41. The wave length of thermal radiations is ———— that of visible light
A. More than B. Lesser than C. Equal to D. None of these
42. Light waves and radio waves are
A. Transverse waves B. Longitudinal waves C. Elastic waves D. None of the above
43. The sound heard after reflection from a rigid obstacle is
A. an echo B. refraction of the sound C. Dispersion D. Diffusion
44. The audible range for human ear is
A. 20 Hz to 2000 Hz B. 20 Hz to 200 Hz
C. 20 Hz to 20,000 Hz D. 20 Hz to 20 kHz
45. The unit of frequency is
A. Meter/second B. Meter C. Second D. Hertz
46. During compression in longitudinal waves
A. Particles of a medium are closer to one another and there is a momentary reduction in
volume of the medium
B. Particles of a medium are further apart than is normal and there is a momentary increase in the volume
C. Particles remains at their normal positions D. None of the above
47. The distance of distinct vision for a normal eye is
A. 25 metres B. 250 centimetres C. 25 centimetres D. 0.25 centimetres
48. When a magnet is broken into two pieces, it acts as a
A. North pole B. South pole C. Magnet D. Non-magnetic substance
49. The S.I. unit of magnetic flux is
A. Tesla B. Weber C. Maxwell D. Gauss
50. The S.I unit of intensity of magnetic field is
A. Weber B. Tesla C. Gauss D. Ampere
51. In India the fast breeder reactor is installed at
A. Trombay B. Kalpakkam C. Tarapur D. Narora
52. Which cannot be included in fossil fuels ?
A. Petroleum B. Natural gas C. Wood charcoal D. Coal
53. Two objects losing the same weight when immersed in water must have the same
A. weight in air B. weight in water C. volume D. density
54. The main source of energy in the biosphere is
A. electricity B. fire wood C. sun D. plants
55. The voltage between any two phases in the three phase system is
A. 1100V B. 400 V C. 220 V D. 110V
56. Dynamo was invented by
A. Newton B. Einstein C. Faraday D. Edison
57. Who was the first chairman of the Atomic Energy Commission of India ?
A. Vikram Sarabhai B. Dr. Homi J. Bhaba C. U.R. Rao D. M.G.K. Menon
58. The planet nearest to the Earth is
A. Venus B. Mars C. Pluto D. Neptune
59. Pasteurization is a process of
A. cooling the milk to 00C B. heating the milk to boiling
C. cooling the milk followed by moderate heating
D. moderate heating followed by cooling.
60. Water freezes at
A. 10°C B. -32°C C. -1°C D. 32°F
61. The X-ray spectra is
A. discrete B. continuous C. series of lines separated by a distance
D. none of these
62. The fact that the compass needle does not point true north was observed first by
A. Newton B. Columbus c. Archimedes D. Edison
63. The base of the binary system is
A. 10 B. 20 C. 4 D. 2
64. The defect in a lens due to its prismatic action is known as
A. chromatic aberration B. spherical aberration
C. Monochromatic aberration D. Myopia
65. In a refrigerator, the refrigerant is
A. Nitrogen B. Oxygen C. Chlorine D. Freon
66. The platinum – Resistance thermometer was first designed by
A. Celsium B. Siemen C. Fahrenheit D. Callender and Griffiths
67. When water in a bucket is whirled fast overhead, the water does not fall out at the top of the motion because
A. the centripetal force on the water is greater than its weight
B. the centripetal force on the water is less than the weight of the water
C. atmospheric pressure counteracts the weight.
D. the reaction of the bucket on the water is zero
68. When milk is churned, cream separates from it due to the
A. Cohesive force B. Centripetal force C. gravitational force D. adhesive force
69. Bat can fly in the dark because
A. they have a better vision in the dark
B. the pupils of their eype are every big
C. They are guided by ultrasonic waves produced by them D. any birds can do so
70. Torricelli is the unit of
A. volume B. pressure C. density D. temperature
71. As a boat moves from fresh water into the salt water, its water mark will
A. go upward B. go down ward C. remain the same
D. depend on the material of the boat
72. In a electric bulb, air is completely removed to prevent
A. efficiency of the bulb B. high resistance of the tungsten
C. high melting point of tungsten D. Oridation of tungsten
73. The small drops of mercury are spherical because the surface area is
A. minimum B. maximum C. zero D. none of the above
74. The surface tension of liquids
A. increases with the rise of temperature B. decreases with the rise of temperature
C. is independent of temperature D. increases randomly with temperature
75. Two pieces of glass plates one over the other with a little water in between them cannot be seperated because of the
A. surface tension B. viscosity C. inertia D. pressure
76. The theory that was developed by Max Planck is
A. wave theory B. quantum theory C. kinetic theory D. none of the above
77. Cobalt – 60 is commonly used in radiation therapy because it emits
A. alpha rays B. beta rays C. gamma rays D. x-rays
78. Which one of the following is a longitudinal wave ?
A. Light wave B. sound wave C. micro wave D. Radio wave
79. One Astronomical unit is the average distance between
A. Earth and the sun B. Earth and the moon
C. Jupiter and the sun D. Pluto and the sun
80. A ‘black hole’ is a body in space which does not allow any radiation to come out. This property is due to its
A. very small size B. very large size C. very high density D. very low density
81. A person is moving towards a plane mirror with a speed of 1m/sec. The image will approach the moving person with a relative speed of
A. ½ m/sec B. 1 m/ sec C. 2 m/sec D. 3 m/sec
82. Domestic electrical wiring is basically a
A. Series connection. B. Parallel connection
C. Combination of series and parallel connections.
D. Neither series nor parallel connections.
83. The working of the quartz crystal in the watch is based on the
A. photo electric effect B. Johnson effect C. Piezo-electric effort D. Edison effect.
84. The term “Mach” is used to measure speed of
A. sound B. wind C. ship D. Aeroplanes
85. Which temperature is equal in Celsius and Fareheits thermometer ?
A. -40 B. 212 C. 40 D. 100
86. The normal temperature of human body on the Kelvin scale is
A. 280 K B. 290 K C. 300 K D. 310 K
87. A man starts walking from a point towards North-East direction. After moving 500 metres he turns towards south and covers a distance 400 metres. At the end he reaches a point.
A. 300 metre North from staring point B. 100 metre North – East from starting point
C. 300 metre East from starting point D. 100 metre North from starting point.
88. A hydrogen – inflated polythene balloon is released from the surface of the earth. As the balloon rises to an altitude up in the atmosphere, it will
A. decrease in size B. flatten into a disc-like shape
C. increase in size D. maintain the same size and shape
89. The nature of light is a
A. wave like B. particle like C. both wave and particle like D. none of these
90. X-rays were discovered by
A. Rutherford B. Bohr C. Rontgen D. Fresnel
91. The property of a liquid owing to which it opposes the relative motion of its various parts is called its
A. surface tension B. critical velocity C. viscosity D. velocity gradient
92. The accumulation of snow on wings of an aeroplane may reduce the lift as
A. weight of the wings changes B. shape of the wings changes
C. overall weight of the aeroplane increases D. none of the above
93. In aeroplanes, we use polaroids to
A. control speed B. control amount of light coming inside
C. control direction D. None of the above
94. The wave theory of light was put forward by
A. Christian Huygens B. Newton C. Max Plank D. Einstein
95. On mixing some detergent with pure water, the cleaning property of water improves because of
A. low surface tension B. low density C. low viscosity D. laminar flow
96. The human ear is
A. more sensitive to sound of low intensity B. less sensitive to sound of low intensity
C. equally sensitive to sound of all intensities D. not sensitive to sound of low intensity
97. If one of the prongs of a turning fork gets broken the vibrations
A. cannot be maintained B. are maintained at the same frequency
C. are maintained at a lower frequency D. are maintained at a higher frequency
98. Which of the following instruments is not used for measuring thermal radiations
A. Bolometer B. Boy’s radio micrometer C. Crooke’s radiometer
D. Pyrometer
99. Which of the following will radiate more heat ?
A. White polished surface B. White rough surface
C.Black polished surface D. Black rough surface
100.Lift was invented by
A. Edison B. Graham Bell C. James watt D. Ottis

Answers
1 B 2 D 3 A 4 A 5 B 6 C 7 B 8 C 9 C 10 A 11 D 12 C 13 A 14 B 15 D 16 A 17 B 18 A 19 B 20 A 21 B 22 C 23 B 24 A 25 C 26 B 27 B 28 C 29 C 30 D 31 C 32 A 33 B 34 A 35 A 36 B 37 B 38 A 39 B 40 A
41 A 42 A 43 A 44 C 45 D 46 A 47 C 48 C 49 B 50 B 51 B 52 C 53 D 54 C 55 B 56 C 57 B 58 A 59 D 60 D 61 B 62 B 63 D 64 A 65 D 66 B 67 A 68 B 69 B 70 B 71 B 72 D 73 A 74 B 75 A 76 B 77 B 78 B 79 A 80 C 81 C 82 B 83 C 84 D 85 A 86 D 87 C 88 D 89 C 90 C 91 C 92 B 93 B 94 A 95 A 96 A 97 A 98 D 99 D 100D

GENERAL SCIENCE PRACTICE QUESTIONS

1. LASER is
A. Light amplification by stimulated emission of radiation.
B. Light amplified by simultaneous emission of radiation
C. Light amplification by super emission of radiation.
D. None of the above.

2. The energy possessed by the water collected in the reservoir of a dam
A. Kinetic energy
B. Mechanical energy
C. Electric energy
D. Potential energy

3. Laws of electrolysis was given by
A. Arrhenius
B. Bronsted – Lowery
C. Faraday
D. Ostwald

4. The unit of electric charge is
A. Ampere
B. Ohm
C. Volt
D. Coulomb

5. In an electrochemical cell, electrons flow from
A. Cathode to anode
B. Anode to cathode
C. Either cathode or anode
D. None of the above

6. The correct form of Einsteins mass-energy equation is _____
A. E = mc
B. E = mc2
C. M = ec
D. m = Ec2


7. Acceleration due to gravity on the moon is the acceleration 1/6th due to gravity on earth. If a balloon filled with the hydrogen is released on the moon
A. falls with acceleration g/6
B. falls with acceleration less than g/6
C. rises with uniform velocity
D. rises with acceleration less than g/6

8. Which mirror is used as rear view mirror in vehicles
A. convex mirror
B. Concave mirror
C. plane mirror
D. metallic mirror

9. Optical fibres are related with
A. communication
B. light
C. computer
D. None of these

10. Brilliance of diamond is due to
A. shape
B. Cutting
C. reflection
D. total internal refection

11. One can not see through fog because
A. fog absorbs light
B. the refractive index of fog is infinity
C. light suffers total reflection at the droplet in a fog
D. light is scattered by droplets in fog.

12. Golden view of sea shell is due to
A. diffraction
B. dispersion
C. polarization
D. reflection

13. Cyclotron is a device to
A. Accelerate neutrons
B. Accelerate electrons
C. Both (A) and (B)
D. None of these

14. If a stationary charge is put inside a magnetic field, then the charge will
A. move in straight line
B. move in circle
C. more in helix
D. remain stationary

15. At the magnetic poles of the earth, a compass needle will be
A. Bent slightly vertical
B. Vertical
C. Horizontal
D. Inclined at 450 to the horizontal

16. When sugar is added to water, the surface tension of sugar solution is
A. More than that of water
B. The same as that of water
C. Less than that of water
D. Uncertain

17. An astronaut can’t hear his companion at the surface of the moon because :
A. Produced frequencies are above the audio frequencies
B. There is no medium for sound propagation
C. Temperature is too during night and too high during day
D. There are too many craters on the surface of the moon

18. The ear phone of a telephone converts
A. Mechanical energy into electrical energy
B. Sound energy into electrical energy
C. Electrical energy into sound energy
D. Electrical energy into mechanical energy

19. Earthquake is measured by
A. Seismograph
B. Electroscope
C. Barometer
D. None of these

20. Pitch of a sound depends upon its
A. wave length
B. Frequency
C. Amplitude
D. Overtones

21. Thermopile is used to
A. Measure electric current
B. Measure potential difference
C. Detect the pressure of heat radiation
D. None of the above

22. Rectifier is used for
A. Giving constant current
B. Giving constant voltage
C. Converting DC to AC
D. Converting AC to DC

23. Most of the light rays inside a tube-light is in the form of ____
A. infrared light
B. visible light
C. ultra-violet light
D. Bright light

24. The triode was designed by
A. Edison
B. Le.De.Forest
C. Flemming
D. Richardson

25. Electromagnetic waves transport
A. Electric charge
B. Alternating current
C. Energy
D. Wave length

26. The back side of the stage of an auditorium should be
A. straight
B. elliptic
C. parabolic
D. None of the above

27. Which of the following pairs are not inter-related to each other ?
A. Carat-gold
B. Decibel-sound
C. Horse power-power
D. Ohm-acceleration

28. Thermal state of a body is defined by
A. Temperature
B. Heat
C. Cold
D. None of the above

29. The temperature of the sun can be calculated from
A. Newton’s law of motion
B. Einstein’s law of relativity
C. Wein’s law of displacement
D. Cannot be calculated

30. The  a- ray and b- ray in radioactivity was found by
A. Madam Curie
B. Rutherford
C. Becquerel
D. Kaufmann

31. The half life of 14C is
A. 5692 × 1010 years
B. 5692 years
C. 6592 years
D. 6592 ×1010 years

32. A binary digit is called
A. word
B. code
C. bit
D. Digit

33. The force keeping the planets in a regular orbit is
A. Electrostatic
B. Magnetic
C. Gravitational
D. Nuclear

34. Venturi meter is used to measure
A. The mass of the liquid
B. The density of the liquid
C. the rate of flow of the liquid
D. None of the above

35. When a soap bubble is charged, it is found to be
A. increased in size
B. Decreased in size
C. of the same size
D. varing in the size depending on the amount of the charge

36. The scientist who was conferred with all the three national awards : Padma Bhushan, Padma Vibhushan and Bharat Ratna.
A. Dr. Vikram Sarabhai
B. Dr. Raja Ramanna
C. Dr. A.P.J. Abdul kalam
D. Dr. Homi.J.Bhabha

37. A cylindrical lens is required to correct
A. Astigmatism
B. Myopia
C. Presbyopia
D. Hyper metropia

38. Skating on ice is possible because of
A. friction
B. regulation
C. sublimation
D. Evaporation

39. Cathode rays consists of
A. Positively charged particles
B. Negatively charged particles
C. Neutral particles
D. None of the above

40. The number of neutrons in an Uranium atom, 238U92 is
A. 92
B. 238
C. 330
D. 146

41. Germanium is
A. conductor
B. Insulator
C. Semi-conductor
D. Metal

42. Electronics is the study of
A. flow of electrons
B. flow of molecules
C. flow of photons
D. flow of elements

43. The smallest particle of a substance that can exist in free state are
A. Atoms
B. Ions
C. Molecules
D. Electrons

44. With rise in temperature, the resistance of metals
A. Decreases
B. Increases
C. Remains same
D. None of the above

45. The resistance of mercury disappears at
A. 00C
B. below 40K
C. Above 40C
D. 1000C

46. Colour of thin films result from
A. Scattering of light
B. Dispersion of light
C. Interference of light
D. Absorption of light

47. The instrument used for electrolysis is
A. Watt meter
B. Volta meter
C. Volt meter
D. Ammeter

48. Friction can be reduced by changing over from
A. potential to kinetic energy
B. sliding to rolling
C. dynamic to static
D. rolling to sliding

49. If the earth is assumed to be a homogenous sphere and if, some how, it contracts to half its present size, the duration of the day will be
A. 6 hours
B. 12 hours
C. 24 hours
D. 48 hours

50. Which of following statements is incorrect ?
A. The mass of a body is not the same as its weight
B. The mass is a measure of quantity of matter whereas weight is a force
C. The mass of a body varies from place to place but its weight remains constant.
D.In the MKS system, mass is expressed in kilogram and weight in Newton.

51. If a conductor is touched by hand, the charge would leak to
A. body of man
B. only to the hand
C. Earth
D. the charge will not leak

52. Diffusion of light in atmosphere takes place due to
A. Carbondioxide
B. Dust particles
C. Helium
D. Water vapour

53. A plant with green leaves placed in red light will appear
A. Black
B. Green
C. Red
D. Violet

54. A tennis ball will bounce
A. higher on hills than on plains
B. higher on plains than on hills
C. equally on hills and plains
D. higher either on hills or on plains depending upon the ground friction.

55. Name the first Indian Astronaut
A. Kalpana Chawla
B. Rakesh Sharma
C. Kalpana Chaudhari
D. Chokila Iyer

56. The invisible water vapour in the atmosphere is termed as –––––––
A. Smog
B. Dewpoint
C. Humidity
D. Hoar frost

57. Meniscus of mercury in capillary is
A. concave
B. convex
C. plane
D. Cylindrical

58. When there are no external forces, the shape of a liquid drop is determined by
A. surface tension of the liquid
B. density of the liquid
C. Viscosity of the liquid
D. temperature of air only

59. A good lubricant should have
A. high viscosity
B. low viscosity
C. moderate viscosity
D. high density

60. A ring shaped piece of metal is heated. If the material expands, the hole will
A. expand
B. contract
C. expand or contract depending on the width of the ring
D. expand or contract depending on the value of the coefficient of expansion.

61. Solar energy is received by the earth through
A. Radiation
B. Conduction
C. Convection
D. Refraction

62. Water pipes burst in severe winter at hill stations because
A. They contract on cooling
B. Water in the pipe expands on freezing
C. Water in the pipes contract
D. Pipes expand on cooling.

63. Which waves are used in sonography ?
A. microwaves
B. infra-red rays
C. sound waves
D. ultrasonic waves

64. Velocity of sound in vacuum (in m/s) is
A. 0
B. 340
C. 156
D. 1000

65. Who said, ‘A body will remain at rest unless an external force acts on the body ?
A. Newton
B. Einstein
C. Archimedes
D. Galileo

66. An echo is heard when minimum distance of the reflecting surface is
A. 10 cm
B. 17 m
C. 34 m
D. 340 m

67. When ice metts in a beaker of water, the level of water in the beaker will
A. increase
B. decrease
C. remain the same
D. first increase then decrease

68. Unit of power is
A. watt
B. Decibel
C. Ampere
D. Volt

69. Insulators are substances with
A. free electrons
B. Bound electrons
C. (A) & (B)
D. None of the above

70. Which of the following electro magnetic waves are used in telecommunication ?
A. x-rays
B. Infrared
C. Microwaves
D. Ultraviolet

71. The radioactive element which is used for finding the age of fossils is ——
A. 6C12
B. 6C14
C. Radio active nitrogen
D. Radio active oxygen

72. The Indira Gandhi Atomic Research Centre is located in ———
A. Maharastra
B. Tamil Nadu
C. Uttar Pradesh
D. Karnataka

73. The velocity of light is maximum in
A. diamond
B. water
C. vacuum
D. glass

74. In radioactivity, the mass number and the atomic number of a radio active nucleus does not change when it emits
A. An alpha particle
B. A beta particle
C. A gamma ray
D. All the three

75. The unit of electric charge is
A. ampere
B. Ohm
C. volt
D. coulomb

76. The distance traveled by a body in unit time is termed as
A. Velocity
B. Acceleration
C. Speed
D. Displacement

77. ———— is used for measuring flow of liquids
A. Ammeter
B. Venturimeter
C. Galvanometer
D. Resonance column

78. Wave theory of light was discovered by ——
A. Issac Newton
B. Christian Huygens
C. Maxwell
D. Theodore Miaman

79. A modern digital computer consists of
A. Hardware only
B. Software only
C. Hardware and software
D. Hardware, software and firmware

80. The refractive index for air is
A. 0
B. 1
C. 2
D. 1.5

81. A red light is used in a traffic signal because
A. It has the longest wavelength and can be easily noticed from a long distance
B. It is beautiful
C. It is visible to people even with bad eye sight
D. None of these

82. Water cannot be used to extinguish fire caused by an electric current because
A. It may cause another short circuit
B. it may cause hydrolysis
C. it may cause electroduction
D. it will spoil the wiring

83. Colour of a light is determined by its
A. intensity
B. amplitude
D. velocity
D. frequency

84. Using a sextant, we can measure the
A. thickness of a paper sheet
B. brightness of a wall at a large distance
C. depth of a mine
D. altitude of the sun

85. If we go to the Himalayas, we feel breathless because
A. it is very cold there
B. the density of air is much less on the hills. So oxygen content in reduced
C. the density of air is high on the hills. This reduces the oxygen content
D. None of these

86. An echo is produced by the ––––– of sound waves
A. refraction
B. reflection
C. absorption
D. diffraction

87. A p-type semi conductor crystal has an excess of
A. Electrons
B. Holes
C. protons
D. none of the above

88. The energy of sun is produced by :
A. oxidation
B. nuclear fission
C. Nuclear fusion
D. Some other source

89. Fish plates are used in railway tracks
A. To avoid tracks being distorted due to temperature fluctuation
B. To control speed of the train
C. to connect two rails
D. to keep the rails equidistant

90. The element used in an electric filament is
A. copper
B. Aluminium
C. iron
D. Tungsten

91. During rusting
A. iron gains weight
B. iron loses weight
C. The weight of iron remains unchanged
D. Iron volatilizes

92. The passenger in a boat are not allowed to stand because
A. this will raise the centre of gravity and the boat will be rocked
B. this will lower centre of gravity and the boat will be rocked
C. the effective weight of system increases
D. of surface tension effects.

93. A fresh egg sinks in pure water but floats in salt water. This is because
A. Saline water is denser than pure water
B. Saline water is lighter than pure water
C. The viscosity of saline water is higher than that of pure water
D. the surface tension of saline water is lower than that of pure water.

94. The planet that has prominent rings around it is
A. Venus
B. Jupiter
C. Mars
D. Saturn

95. For measuring temperature near absolute zero, thermometer used is –––––––
A. Thermo-electric thermometer
B. Radiation thermometer
C. Magnetic thermometer
D. Resistance thermometer

96. Light from the sun reaches us in nearly
A. 200 seconds
B. 300 seconds
C. 500 seconds
D. 400 seconds

97. Which of the following heavenly bodies do not belong to the solar system
A. planets
B. pulsars
C. Comets
D. Asteroids

98. The colour of the ocean appears to be blue because the sun-light falling on it is
A. reflected
B. refracted
C. absorbed
D. scattered

99. Alternating current is converted to direct current by a
A. rectifier
B. oscillator
C. transformer
D. motor

100.Which of the following is not a primary colour?
A. blue
B. green
C. red
D. black

Answers
1 A 2 D 3 C 4 D 5 B 6 B 7 A 8 A 9 A 10 D 11 D 12 C 13 B 14 D 15 B 16 A 17 B 18 C 19 A 20 B 21 C 22 D 23 C 24 B 25 C 26 C 27 D 28 A 29 C 30 B 31 B 32 C 33 C 34 C 35 A 36 C 37 A 38 A 39 B 40 D
41 C 42 A 43 C 44 B 45 B 46 C 47 B 48 B 49 A 50 C 51 C 52 B 53 A 54 A 55 B 56 C 57 B 58 A 59 A 60 A 61 A 62 D 63 D 64 A 65 A 66 B 67 C 68 A 69 B 70 C 71 B 72 B 73 C 74 C 75 D 76 C 77 B 78 B 79 D 80 B 81 A 82 A 83 D 84 D 85 B 86 B 87 B 88 C 89 B 90 D 91 A 92 A 93 A 94 D 95 C 96 C 97 B 98 D 99 A 100 D