## general science

### Physics MCQ Questions and Answers Page - 10

1.
 A rectangular coil of copper wire is rotating in a magnetic field. The direction of the induced current changes once in each  ? A Two revolutions B One revolution C Half revolution D One fourth revolution Answer : C Explanation :
2.
 What will be equivalent resistance of two resistors  R1  and  R2  when connected in series  ? A $R_{1}&space;-&space; B $R_{1}&space;+&space; C $\frac{R_{ D $\frac{2R Answer : B Explanation :
3.
 The phenomena of electromagnetic induction is  ____________ . A The process of charging a body B The process of generating magnetic field due to a current passing through a coil C Induced current in a coil due to relative motion between a magnet and the coil D The process of rotating a coil of an electric motor Answer : C Explanation :
4.
 The resistance of a metal conductor is  ____________ . A Directly proportional to its length B Directly proportional to its cross sectional area C Inversely proportional to its length D No option is correct Answer : A Explanation :
5.
 While moving from one end to another end inside a solenoid, its magnetic field  ____________ . A Increases B Decreases C Remains same D First increases then decreases Answer : C Explanation :
6.
 Which of the following is Fleming’s right hand rule  ? A Induced current is directed in the direction of movement of conductor B Magnetic field is directed in the direction of movement of conductor C Magnetic field is directed in the direction of induced current D Movement of conductor, Magnetic field and induced current are perpendicular to each other Answer : D Explanation :
7.
 What is the direction of Magnetic field lines in a magnet  ? A East pole to West pole B West pole to East pole C North pole to South pole D South pole to North pole Answer : C Explanation :
8.
 Which of following property of a proton cannot change while it moves freely in magnetic field  ? A Speed B Velocity C Momentum D Both speed and velocity Answer : A Explanation :
9.
 When the direction of motion of coil is perpendicular to the electromagnetic field, then the value of induced current is  ___________ . A Minimum B Maximum C Neither minimum nor maximum D No option is correct Answer : B Explanation :
10.
 Which among the following is  NOT  a conductor of electricity  ? A Mercury B Manganese C Iron D Ebonite Answer : D Explanation :
11.
 Which of the following statement is  INCORRECT  ? A An electric motor converts electric energy into mechanical energy B An electric generator works on the principle of electromagnetic induction C The magnetic field at the centre of a long circular coil carrying current will be parallel straig D A wire with green insulation is usually the live wire Answer : D Explanation :
12.
 There is a circular coil having  n  turns. The field produced is how many times larger than produced by a coil of single turn  ? A $n$ B $n^{2}$ C $\frac{n}{2}$ D $\frac{n^{2}}{2}$ Answer : A Explanation :
13.
 When two resistors are connected in parallel, they have  ___________ . A Same current B Same potential difference C Different potential difference D Both same current and different potential difference Answer : B Explanation :
14.
 What precaution should be taken to avoid the overloading of domestic electric circuits   ? A Fuse should be connected in the circuit. B Too many appliances should not be connected in single circuit. C Faulty appliances should not be connected in the circuit. D All options are correct. Answer : D Explanation :
15.
 What is the effective resistance (in Ω)  of two resistors  20 Ω  and  30 Ω  connected in parallel  ? A 50 B 12 C 24 D 25 Answer : B Explanation :
16.
 For which diode is used  ? A Modulation B Oscillation C Amplification D Purification Answer : D Explanation :
17.
 Who among the following developed the technology of underground nuclear explosion  ? A Dr. Homi J. Bhabha B Dr. Vikram Sarabhai C Dr. Raja Ramanna D Dr. P. K. Iyengar Answer : A Explanation :
18.
 The mass of a star is two times the mass of the Sun. how it will come to an end  ? A Neutron Star B Black hole C White Dwarf D Red Giant Answer : A Explanation :
19.
 On which of the following techniques photo-state machine works  ? A Magnetic Image-Making B Thermal Image-Making C Electrostatic Image-Making D Electromagnetic Image-Making Answer : C Explanation :
20.
 “curie” is unit of  : A Radioactivity B Temperature C Heat D Energy Answer : A Explanation :
21.
 Which of the following is used in oven  ? A X-rays B UV rays C Microwaves D Radio waves Answer : C Explanation :
22.
 Which of the following is used for regulated electric supply  ? A Zener diode B Junction diode C Gun diode D Tunnel diode Answer : A Explanation :
23.
 The shape of our milky way galaxy is A Circular B Elliptical C Spiral D None of the above Answer : D Explanation :
24.
 The different colours of different stars are due to the variation of A Temperature B Pressure C Density D Radiation from them Answer : A Explanation :
25.
 Solar energy is converted into chemical energy during A Transpiration B Photosynthesis C Diffusion D Osmosis Answer : B Explanation :
26.
 The term  ‘equinox’  means A The path which the Earth takes around the Sun B The axis of the Earth around which it rotates C When the day and night are of equal duration D The time when the Sun seems to be going round and round in the sky in the Arctic but does not go Answer : C Explanation :
27.
 Which of the following occurred first  ? A Albert Einstein propounded the General Theory of Relativity B Max Planck unveiled the Quantum Theory C Guglielmo Marconi sent out the first wireless signals D Wright brothers successfully flew an aircraft Answer : C Explanation :
28.
 Electrostatic precipitator is used to control the pollution of A Air B Water C Noise D Thermal Answer : A Explanation :
29.
 ‘Cryogenics’ is a science dealing with A High temperatures B Low temperatures C Friction and wear D Growth of crystals Answer : B Explanation :
30.
 The mass-energy relation is the outcome of A Quantum theory B General theory of relativity C Field theory of energy D Special theory of relativity Answer : D Explanation :
31.
 Nuclear reactors used to produce electricity are based on A Nuclear fission B Nuclear fusion C Cold fusion D Superconductivity Answer : A Explanation :
32.
 Remote-sensing device has an inbuilt source of A X-ray B G-ray C Ultraviolet ray D Infrared ray Answer : D Explanation :
33.
 Energy of Ultraviolet rays is greater than A Infra-red rays B Gamma rays C X-rays D Cosmic rays Answer : A Explanation :
34.
 According to the theory of relativity, which of the following always remains constant  ? A Length of an object B Time C Space D Velocity of light Answer : D Explanation :
35.
 Atomic power plant works on the principle of A Fission B Fusion C Thermal combustion D Combined effect of all the above three Answer : A Explanation :
36.
 Which of the following is  NOT  a property of heavy water  ? A Boiling point of heavy water is lower that or ordinary water B Density of heavy water is higher than that of ordinary water C Freezing point of heavy water is higher than that of ordinary water D It produces corrosion Answer : A Explanation :
37.
 Curie point is the temperature at which A Matter becomes radioactive B A metal loses magnetic properties. C A metal loses conductivity D Transmutation of metal occurs. Answer : B Explanation :
38.
 The scientist who first sent electromagnetic waves to distant places is A James Clerk Maxwell B Heinrich Hertz C Thomas Alva Edison D John Logic Baird Answer : C Explanation :
39.
 Which type of reaction produces the most harmful radiation  ? A Fusion reaction B Fission reaction C Chemical reaction D Photo – Chemical reaction Answer : B Explanation :
40.
 In MRI machine, which one of the following is used  ? A Sound wave B ‘X’-ray C Ultra-sound wave D Magnetic wave Answer : D Explanation :
41.
 Gamma rays have greatest similarity with A $\alpha&space;-&space B $\beta&space;-&space;r C $X&space;-&space;rays$< D $U.&space;V.&space;-&a Answer : C Explanation :
42.
 In a nuclear reactor. One of the following is used as a fuel. A Coal B Uranium C Radium D Diesel Answer : B Explanation :
43.
 After long periods of use, a grey spot develops on the inside of a bulb. This is because A The tungsten filament evaporates and collects there B The heat of the bulb scorches the glass at the top C Dust inside the bulb condenses on the top D Glass undergoes a change due to the heat Answer : C Explanation :
44.
 Forged documents are detected by A Ultraviolet rays B Infra-red rays C Beta rays D Gamma rays Answer : A Explanation :
45.
 The radiation initially produced in fluorescent tube is A Infrared B Ultraviolet C Microwaves D X-rays Answer : B Explanation :
46.
 The important unit of a microprocessor is A ALU B Array of registers C Control unit D All of the above Answer : D Explanation :
47.
 In nuclear reactor, heavy water is used as  : A Coolant B Fuel C Moderator D Atomic smasher Answer : C Explanation :
48.
 Which of the following is NOT a part of a CRT  ? A Phosphor screen B Shadow Mask C Electron gun D Gas plasma Answer : D Explanation :
49.
 In the remote control of television, electromagnetic waves used are A Ultraviolet B Microwave C Radio-wave D Infrared Answer : D Explanation :
50.
 A radioactive substance does not undergo any change  (in mass or charge) during A Gamma-emission B Oxidation C Alpha-emission D Beta-emission Answer : A Explanation :
51.
 Radioactive elements can be traced out in living cell through a technique called A Centrifugation B Chromatography C Auto radiography D All the above Answer : C Explanation :
52.
 A  NOT  gate can be implemented by  : A A single diode B Two diodes C A single resistor D A single transistor Answer : D Explanation :
53.
 Photon is the fundamental unit/quantum of A Gravitation B Electricity C Magnetism D Light Answer : D Explanation :
54.
 The term reactor referred to in waste water treatment is A Vessel B Settling tank C Clarifier D Aeration tank Answer : D Explanation :
55.
 Alpha particle is the nucleus of an atom of A Lithium B Hydrogen C Helium D Oxygen Answer : C Explanation :
56.
 Which of the following supports particle nature of photons  ? A Diffraction B Polarization C Photoelectric effect D Interference Answer : C Explanation :
57.
 What is a neuron  ? A Basic unit of energy B Particle released during radioactivity C The anti-particle of neutron D Basic unit of nervous system Answer : D Explanation :
58.
 Matter waves are A De Broglie waves B Electromagnetic waves C Transverse waves D Longitudinal waves Answer : A Explanation :
59.
 According tp special theory of relativity the mass of a particle A Increases with increase in velocity with respect  to an observer. B Decreases with increase in velocity. C Decreases with decrease in velocity. D Is independent of its velocity. Answer : A Explanation :
60.
 A moving neutron collides with a stationary  $\alpha$– particle. The fraction of the kinetic energy lost by the neutron is A $\frac{1}{4}$ B $\frac{1}{16}$ C $\frac{9}{25}$ D $\frac{16}{25}$ Answer : D Explanation :
61.
 The unit of Planck’s constant is A $Js$ B $Js^{-2}$ C $\frac{J}{s}$ D $Js^{2}$ Answer : A Explanation :
62.
 Which of the following options correctly explains the term heat budget ? A It is a mode of transfer of heat through matter by molecular activity. B It is the balance between incoming and outgoing radiation C It is the radiation from the earth in the form of long waves. D It is the amount of heat which the surface of earth receives from the sun. Answer : B Explanation :
63.
 The abbreviation  LHC  stands for which machine  ? A Light Heat Collider B Large Hadron Collider C Long Heavy Collider D Large High Collider Answer : B Explanation :
64.
 Planck’s constant has the dimensions of  : A Energy B Linear momentum C Angular momentum D Force Answer : A Explanation :
65.
 In which region of electromagnetic spectrum does the Lyman series of hydrogen atom lie  ? A Visible B Infrared C Ultraviolet D X-ray Answer : C Explanation :
66.
 Beta rays emitted by a radioactive material are A The electrons orbiting around the nucleus B Charged particles emitted by nucleus C Neutral particles D Electromagnetic radiations Answer : B Explanation :
67.
 If an electron and a photon have the same wavelength, then they will have the same A Velocity B Linear momentum C Angular momentum D Energy Answer : B Explanation :
68.
 Curie is an unit of A Radioactivity B Energy of Gamma rays C Intensity of Gamma rays D Work function Answer : A Explanation :
69.
 Energy travels from Sun to Earth through A Conduction B Convection C Radiation D Modulation Answer : C Explanation :
70.
 The commonly used coolant in refrigerators is A Ammonia B Nitrogen C Freon D Oxygen Answer : C Explanation :
71.
 Sending a frame to a group of stations is known as A Single casting B Spreading C Multicasting D Casting Answer : C Explanation :
72.
 Which is the most suitable unit for expressing nuclear radius  ? A Micron B Nano-meter C Fermi D Angstrom Answer : C Explanation :
73.
 Which among the following waves is used for communication by artificial satellites  ? A Micro waves B Radio waves C A. M. D Frequency of  1016 series Answer : A Explanation :
74.
 What is found in frequency modulation  ? A Fixed frequency B Fixed dimension C Change in frequency and dimension D Change in dimension only Answer : A Explanation :
75.
 Crooke’s tube is used to produce A Radio waves B Micro waves C X-rays D Gamma rays Answer : C Explanation :
76.
 Why are we able to hear short wave broadcasts better than long wave broadcasts  ? A Short waves are more energetic than long waves . B Short waves are unaffected by atmospheric disturbances. C Short waves broadcasts are made by nearby radio stations. D By convention, short waves are meant for long distances, whereas long waves are reserved for shor Answer : A Explanation :
77.
 When a vehicle passes,  TV  reception gets distorted. This is because A Metal reflects radio-waves B Spark plug creates electromagnetic disturbances C Vehicle pollution affects the performance of the  TV  components D Modern vehicles use electro-ignition system Answer : B Explanation :
78.
 The atmospheric layer reflecting radio waves is called A Ozonosphere B Ionosphere C Stratosphere D Mesosphere Answer : B Explanation :
79.
 What is the full form of  ‘AM’  regarding to radio broadcasting  ? A Amplitude movement B Anywhere movement C Amplitude Matching D Amplitude Modulation Answer : D Explanation :
80.
 Which of the following celestial bodies contains abundant quantities of helium-3, a potential source of energy  ? A Earth B Moon C Venus D Saturn Answer : B Explanation :