GENERAL SCIENCE MCQs

1. Jet engines are
(a) rotary engines
(b) turbine engines
(c) external combustion engines
(d) reaction engines

2. In an engine run on diesel, ignition is caused through
(a)friction
(b) automatic starter
(c)spark plug
(d) compression

3. In an electronic watch, the component corresponding to the pendulum of a pendulum clock is
(a)Transistor
(b) Balance Wheel
(c) Crystal Oscillator
(d) Diode

4. The hydraulic brakes used in automobiles is a direct application of ?
(a) Archimedes’ Principle
(b) Toricellian law
(c) Bernoulli’s theorem
(d) Pascal’s law

5. Which of the following statements is correct?
(a) Dynamo converts electrical energy into heat energy and electric motor converts mechanical energy into electrical energy.
(b) Dynamo converts mechanical energy into electrical energy and electric motor converts electrical energy into mechanical energy.
(c) Both dynamo and electric motor convert electrical energy into mechanical energy.
(d) Both dynamo and electric motor convert mechanical energy into electrical energy.

6.. An electron microscope gives higher magnification than an optical microscope because
(a) it uses more powerful lenses.
(b) the velocity of electrons is smaller than that of visible light.
(c) the electrons have more energy than the light particles.
(d) the wavelength of electrons is smaller as compared to the wavelength of visible light.

7. The conversion of electrical energy into chemical energy is observed in ?
(a) fan
(b) storage battery
(c) heater
(d) incandescent bulb

8. The most efficient engine is ?
(a) Petrol
(b) Diesel
(c) Electric
(d) Steam

9. The tape of a tape recorder is coated with
(a) Zinc oxide
(b) Copper sulphate
(c) Mica
(d) Ferromagnetic powder

10. When a coil is rotated in magnetic field, induced current is generated in the coil. This principle is used in making ?
(a) electromagnet
(b) electric motor
(c) electric generator
(d) electric watt meter

11. An ordinary tube light used for lighting purposes
contains
(a) fluorescent material and an inert gas
( b) one filament, reflective material and mercury vapour
(c) fluorescent material and mercury vapour
(d) two filaments, fluorescent material and mercury vapour

12. The term ‘Black Box’ is more commonly used in relation to which of the following?
(a) It is a box in which high grade uranium is kept to prevent radiation.
(b) It is a time capsule in which records of important events are kept to be opened at a later date,
(c) It is a flight recorder in an aero plane.
(d)None of these

13. The lightning conductor used in building, protects the building by
(a) dissipating the electric charge away from the building
(b) conducting the lightning safely to the ground
(c) absorbing the electric charge
(d) None of these

14. Sodium vapour lamps are preferred over incandescent lamp because of
(a) higher tolerance to voltage fluctuation
(b) higher intensity of illumination
(c) easy installation
(d) None of these

15. The principle of working of periscope is based on
(a) reflection only
(b) refraction only
(c) reflection and refraction
(d) reflection and interference

16. The working of the quartz crystal in the watch is based on
(a) Johnson effect
(b) Photoelectric effect
(c)Edison effect
(d) Piezo electric effect

17. A handwritten message can be instantly transmitted as such to any part of the world through
(a) Speed post
(b) Telex
(c)Electronic mail
(d) FAX

18. Which of the following combinations of aperture and shutter speed of a camera will allow the maximum exposure?
(a) F-5.6,1/l000
(b) F-8,l/250
(c) F-16,l/l25
(d) F-22,1/60

19. Hardware is related to?
(a) calculator
(b) computers
(c) acids
(d) heavy metals

20. Which of the following best explains the phenomenon ‘Simple Harmonic Motion’?
(a) Cylinder
(b) Disc
(c) Pendulum
(d) None of these

21. Distant objects can be seen with the help of
(a) chronometer
(b) microscope
(c)telescope
(d) spectroscope

22. The safety fuse should have
(a) high resistance and high melting point
(b) high resistance and low melting point
(c) low resistance and high melting point
(d) low resistance and low melting point

23. Greenhouse is?
(a) a building chiefly of glass in which the temperature is very low.
(b) a building in which green plants are cultivated.
(c) a building chiefly of glass in which the temperature is maintained within the desired range.
(d) None of these

23. Given below are some of the home appliances:
1. 1/8 H.P. Water pump
2. Fluorescenttubelight
3. Room heater
4. Night lamp
Which of the following is the correct sequence in decreasing order of the wattage of the above?
(a) 2,1,3,4
(b) 3,1,2,4
(c)3,2,1,4
(d) 4,2,1,3

25. Which of the following is/are true regarding the third (thicker) pin in a 3-pin plug?
1. It ensures better electrical contact.
2. It is connected to the body of the electrical device.
3. It is connected to the earth terminal.
4. It is connected to the neutral terminal.
(a) 1 and2
(b) 2 and 3
(c) 1 and3
(d) 4only

26. Consider the following statements about a thermos flask:
1. It is a practical device in which the beat flowing into or out of the system by conduction, convection or radiation is reduced as much as possible.
2. It consists of a double – walled glass vessel.
3. The heat transfer by convection is minimized by silvering the surfaces and the radiation is minimized by evacuating the space between the walls.
Of these, the correct ones are
(a) l and 2
(b) 2 and 3
(c) l and 3
(d) l,2 and 3

27. Which of the following are true regarding the compact fluorescent tubes now available in market for home use?
1. They use less power (about 20%) compared to filament type bulbs for same amount of light.
2. They operate at higher voltages.
3. They are narrower and shorter than common fluorescent tubes.
(a) l and 2
(b) 2 and 3
(c) 1 and 3
(d) 1,2 and 3

28. In an ordinary dry cell, the electrolyte is
(a) sulphuric acid
(b) manganese dioxide
(c) ammonium chloride
(d) zinc

29. Which of the following pairs of materials serves as electrodes in chargeable batteries commonly used in devices such as torch lights, electric shavers etc. ?
(a) Iron and cadmium
(b) Nickel and cadmium
(c) Lead peroxide and lead
(d) Zinc and carbon

30. The mixed oxide fuel is used for which of the following?
(a) Nuclear Reactors
(b) Aero planes
(c) Cryogenic Engines
(d) PSLV rockets

31. Conversion of chemical energy into electrical energy occurs in ?
(a)dynamos
(b) electric heaters
(c)battery
(d) atomic bombs

32. In the ordinary fire extinguisher, carbon dioxide is generated by the reaction of ?
(a) marble powder and dilute HCL
(b) magnesite and dilute HCL
(c) limestone and dilute Sulphuric Acid
(d) sodium bicarbonate and dilute Sulphuric Acid

33. Which of the following take place when the subject speaks untruth while being tested by the polygraph instrument?
1.. His blood pressure goes up.
2. His pulse quickens.
3. His skin darkens.
4. He sneezes.
(a) l and 2
(b) 3 and 4
(c) l,2 and 3
(4) 2,3 and 4

34. What is the function of a microprocessor in a computer?
(a) It allows the key board to write on the computer.
(b) It allows the outputs to be taken from a computer.
(c) It performs all the functions of a CPU (Central Processing Unit).
(d) None of these

35.Teletext means?
(a) the process of convening black & white TV sets into coloured ones.
(b) flashing of telephone conversation on TV screen.
(c) flashing the text of the message on the telex machine.
(d) flashing of the text of news and information on the TV screen.

36. Which of the following statements about a refrigerator is/are correct?
1. It converts electrical energy into heat energy.
2. It converts electrical energy into mechanical energy.
3. It transfers heat from a high temperature to a low temperature.
4. It transfers heat from a low temperature to a high temperature.
(a) 1 and3
(b)2 and 3
(c) 1 and 4
(d) 4 only

37. Which of the following statements are true regarding transmission of television programmes?
1. Picture is transmitted with velocity of light.
2. Sound is transmitted with velocity of sound.
3. Sound is transmitted with velocity of light.
4. Different colours of the picture.are transmitted with different velocities.
(a) l and 3
(b) 1,2 and 3
(c) 2,3 and 4
(d) l,3 and 4

38. The anode in a dry cell consists of
(a) graphite
(b) zinc
(c) copper
(d)cadmium

39. The technique used to transmit audio signals in television broadcasts is
(a) Amplitude Modulation
(b) Frequency Modulation
(c) Pulse Code Modulation
(d) Time Division Multiplexing

40 Floppy disc in a computer system is
(a) compiler
(b) core memory
(c) software
(d) device for storing and retrieving data

41. The best colour (s) for a sun umbrella will be
(a)black
(b) black on top and white on the inside
(c)white on top and black on the inside
(d) printed with all the seven colours of rainbow

42. Which one of the following can be used to confirm whether drinking water contains a gamma emitting isotope or not?
(a) Spectrophotometer
(b) Microscope
(c) Scintillation counter
(d) Lead plate

43. The following processes take place during the
launching of a rocket:
1. Rocket fuel is burnt.
2. Gases are produced.
3. Rocket moves in the forward direction.
4. Gases come out with momentum in back ward direction.
The correct sequential order in which the above processes occur, is
(a) 1,2,3,4
(b) 1,3,2,4
(c) 1,2,4,3
(d) 1,3,4,2

44. A computer can be freely programmable
(a) if it is of a digital type
( if it is controlled synchronously
(c) if it contains a read only memory (ROM)
(d) if it contains a random access memory(RAM)

45. Which of the following polymers is widely used for making bullet proof material?
(a) Polyethylene
(b) Polyamides
(c) Polyvinyl chloride
(d) Polycarbonates

46. What is a flow chart in computer terminology?
(a) A graphical representation of a sequence of operations in a computer program
(b) A circular chart used for computer languages
(c) A debugging programme.
(d) None of these

47. A transistor is most likely to be found in a
(a)wrist watch
(b) fuse
(c)hearing aid
(d) fluorescent lamp

48. Ball bearings are used to reduce friction by
(a) applying lubricants to the balls used
(b) reducing the area of contact with the use of metallic balls
(c) increasing the area of contact with the use of metallic balls
(d)None of these

49. Aviation fuel for jet aeroplanes consists of purified
(a)petrol
(b) kerosene
(c)gasoline
(d) diesel

50. Recoil of a gun is an example of
(a) conservation of mass
(b) conservation of energy
(c) conversion of Potential Energy into Kinetic Energy
(d) conservation of linear momentum

ANSWERS

1.D 2. D 3. C 4. D 5. B 6.D 7. B 8. C 9. D 10. C
11.D 12. C 13. B 14. B 15. C 16. D 17. D 18. B 19. B 20. C
21. C 22. B 23. C 24. B 25. B 26. A 27. D 28. C 29. B 30. C
31. C 32. D 33. A 34. C 35. D 36. C 37. A 38. A 39. C 40. D
41. C 42. C 43. C 44. C 45. A 46. A 47. C 48. B 49. A 50. D