[{"id":114488,"question":"The superposition of the two waves of same frequency and amplitude travelling in the same direction gives rise to an effect called:","choices":[{"text":"Diffraction","value":"A"},{"text":"Interference","value":"B"},{"text":"Polarization","value":"C"},{"text":"Dispersion","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":114486,"question":"The locus of all points in a medium having same phase of vibration is called:","choices":[{"text":"Crest","value":"A"},{"text":"Trough","value":"B"},{"text":"Wavelength","value":"C"},{"text":"Wavefront","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":114484,"question":"According to Huygen's principle:","choices":[{"text":"Light travel in straight line","value":"A"},{"text":"Light is a transvers wave","value":"B"},{"text":"Light has dual nature","value":"C"},{"text":"All point on the primary wavefront are the sources of secondary wavelets","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":114483,"question":"The cause of mirage observed in deserts in bright sunlight is due to:","choices":[{"text":"Refraction of light","value":"A"},{"text":"Reflection of light","value":"B"},{"text":"Scattering of light","value":"C"},{"text":"Total internal reflection of light","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":114482,"question":"The velocity of light in vacuum can be changed by changing:","choices":[{"text":"Frequency","value":"A"},{"text":"Amplitude","value":"B"},{"text":"Wavelength","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":114481,"question":"The image of the tip of a needle is never sharp because of","choices":[{"text":"Polarization of light","value":"A"},{"text":"Interference of light","value":"B"},{"text":"Diffraction of light","value":"C"},{"text":"Reflection of light","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":114479,"question":"Which one the following gives three regions of electromagnetic sepctrum in order of increasing wavelength?","choices":[{"text":"Gamma rays, micro waves, visible light","value":"A"},{"text":"Radio waves, ultraviolet waves, X-rays","value":"B"},{"text":"Ultraviolet rays, Infrared rays, micro waves","value":"C"},{"text":"Visible light, gamma rays, radio waves","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":114477,"question":"Huygen's theory cannot explain:","choices":[{"text":"Diffraction","value":"A"},{"text":"Interference","value":"B"},{"text":"Polarization","value":"C"},{"text":"Photoelectric effect","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":114476,"question":"The contrast in the fringes in an interference pattern depends upon","choices":[{"text":"Fringe width","value":"A"},{"text":"Relative intensities of the two sources","value":"B"},{"text":"Distance between the slits","value":"C"},{"text":"Wavelength","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":114474,"question":"If yellow light emitted by sodium lamp in Young's double slit experiment is replaced by blue light of the same intensity:","choices":[{"text":"Fringe width will decrease","value":"A"},{"text":"Fringe width will increase","value":"B"},{"text":"Fringe width will remain unchanged","value":"C"},{"text":"Fringe will become less intense","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":114473,"question":"Which one of the following phenomenon cannot be explained on the bases of Huygen's theory?","choices":[{"text":"Refraction","value":"A"},{"text":"Reflection","value":"B"},{"text":"Diffraction","value":"C"},{"text":"Formation of spectrum","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":114472,"question":"Light appears to travel in straight line because","choices":[{"text":"It is not absorbed by the atmosphere","value":"A"},{"text":"It is refracted by the atmosphere","value":"B"},{"text":"Its wavelength is very small","value":"C"},{"text":"Its velocity is very large","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":114471,"question":"Star twinkle due to","choices":[{"text":"The fact that they do not emit light continously","value":"A"},{"text":"The refractive index of earth's atmosphere fluntuates","value":"B"},{"text":"The star's atmosphere absorbs its light intermittently","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":114460,"question":"A prism splits a beam of white light into seven component colors. This is so because","choices":[{"text":"Phase of different colors is different","value":"A"},{"text":"Amplitude of different colors is different","value":"B"},{"text":"Energy of different colors is different","value":"C"},{"text":"Velocity of different colors is different","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":33997,"question":"The main reason for the high speed of bullet train is","choices":[{"text":"Magnetic effect","value":"A"},{"text":"Reduced friction","value":"B"},{"text":"Design of train","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":33995,"question":"A bullet train move with the velocity of","choices":[{"text":"400 Kmh<sup>-1</sup>","value":"A"},{"text":"460 Kmh<sup>-1</sup>","value":"B"},{"text":"500 Kmh<sup>-1</sup>","value":"C"},{"text":"510 Kmh<sup>-1</sup>","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":33994,"question":"A material most suitable to make the permanent magnet are","choices":[{"text":"High retentivity","value":"A"},{"text":"Large coercive current","value":"B"},{"text":"Small domain friction","value":"C"},{"text":"a and b","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":33993,"question":"The area of the loop is the dissipated energy which do work against friction of domains is called","choices":[{"text":"Current loss","value":"A"},{"text":"Voltage loss","value":"B"},{"text":"Hysteresis loss","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":33991,"question":"The energy need to magnetize and demagnetize the specimen during the each cycle of magnetizing current is","choices":[{"text":"Value of current","value":"A"},{"text":"Value of demagnetizing current","value":"B"},{"text":"Value of magnetic flux density","value":"C"},{"text":"Area of the loop","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":33989,"question":"Hysteresis is the loop in which the material is magnetized and its curve never pass through","choices":[{"text":"The same line","value":"A"},{"text":"One side of origin","value":"B"},{"text":"Origin","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":33987,"question":"A current which demagnetize the material completely is called","choices":[{"text":"Applied current","value":"A"},{"text":"Coercive current","value":"B"},{"text":"Maximum current","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":33985,"question":"Remanance or Retentivity is the phenomenon in which the material still remains strongly magnetized when curve is","choices":[{"text":"Increase to maximum","value":"A"},{"text":"Reduce to minimum","value":"B"},{"text":"Reduce to zero","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":33984,"question":"The saturation of the material reached when magnetic flux density changes from","choices":[{"text":"Zero to minimum value","value":"A"},{"text":"Zero to maximum value","value":"B"},{"text":"Maximum to zero value","value":"C"},{"text":"Minimum to negative value","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":33983,"question":"In the phenomenon of hysteresis, the magnetism and magnetizing current behaves as","choices":[{"text":"I lags","value":"A"},{"text":"1 leads B","value":"B"},{"text":"I &amp; B becomes equal","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":33982,"question":"The curie temperature of iron is","choices":[{"text":"600 C<sup>o</sup>","value":"A"},{"text":"650 C<sup>o</sup>","value":"B"},{"text":"700 C<sup>o</sup>","value":"C"},{"text":"750 C<sup>o</sup>","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":33981,"question":"A temperature at which the material losses its orderliness is know as","choices":[{"text":"Ambient temperature","value":"A"},{"text":"Curie temperature","value":"B"},{"text":"Highest temperature","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":33979,"question":"Hard magnetic materials are","choices":[{"text":"Iron","value":"A"},{"text":"Steel","value":"B"},{"text":"Alnico","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":33978,"question":"A special alloy called Alnico is known as","choices":[{"text":"Soft magnetic material","value":"A"},{"text":"Hard magnetic material","value":"B"},{"text":"In between soft and hand magnetic material","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":33977,"question":"The combination of solenoid and a specimen of iron inside it make a power full magnet called","choices":[{"text":"Horse shoe magnet","value":"A"},{"text":"Bar magnet","value":"B"},{"text":"Electromagnet&nbsp;","value":"C"},{"text":"10<sup>-10</sup> to 10<sup>18</sup>","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":33976,"question":"Each domain contains the atoms of range of","choices":[{"text":"10<sup>-10</sup> to 10<sup>18</sup>","value":"A"},{"text":"10<sup>10</sup> to 10<sup>16</sup>","value":"B"},{"text":"10<sup>12</sup> to 10<sup>17</sup>","value":"C"},{"text":"10<sup>12</sup> to 10<sup>16</sup>","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":33975,"question":"The domains are the small regions of the order of","choices":[{"text":"Millimeter&nbsp;","value":"A"},{"text":"Micrometer","value":"B"},{"text":"Micron","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":33973,"question":"Ferromagnetic materials are those in which atoms cooperate with each other","choices":[{"text":"Weakly","value":"A"},{"text":"Strongly","value":"B"},{"text":"Moderately","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":33972,"question":"The motion of a charged nucleus also produces a magnetic field which is","choices":[{"text":"Weaker than orbital electrons","value":"A"},{"text":"Stronger than orbital electrons&nbsp;","value":"B"},{"text":"Equal than orbital electrons&nbsp;","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":33971,"question":"The examples of diamagnetic substances&nbsp;","choices":[{"text":"Water","value":"A"},{"text":"Copper","value":"B"},{"text":"Antimony","value":"C"},{"text":"All of them","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":33970,"question":"Diamagnetic substances are those in which","choices":[{"text":"Spin and orbital motions are supported","value":"A"},{"text":"Spin and orbital motions are opposed&nbsp;","value":"B"},{"text":"Resultant of spin and orbital motion is zero","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":33940,"question":"Paramagnetic substances are those in which","choices":[{"text":"Spin and orbital motions are supported","value":"A"},{"text":"Spin and orbital motions are opposed","value":"B"},{"text":"Spin and orbital motions supported a little","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":33938,"question":"An atom in which there is a resultant magnetic field behave like a","choices":[{"text":"Tiny magnet","value":"A"},{"text":"Magnetic dipole","value":"B"},{"text":"No magnet","value":"C"},{"text":"a and b","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":33937,"question":"The magnetism produced by electrons within an atom is due to","choices":[{"text":"Spin motion","value":"A"},{"text":"Orbital motion","value":"B"},{"text":"Spin and orbital motion","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":33935,"question":"The magnetism produced by electrons within an atom from motion/motions of electron.","choices":[{"text":"One motion","value":"A"},{"text":"Two motions","value":"B"},{"text":"Three motions","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":33932,"question":"The magnetic field produced due to circulating currents. The idea was first given by&nbsp;","choices":[{"text":"Faraday","value":"A"},{"text":"Ampere","value":"B"},{"text":"Lenz","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":2}]