[{"id":9218,"question":"Pure form of semiconductor is called","choices":[{"text":"Extrinsic semiconductor","value":"A"},{"text":"Intrinsic semiconductor","value":"B"},{"text":"N type","value":"C"},{"text":"P type material","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":9217,"question":"A valance band in solids is","choices":[{"text":"Always completely filled","value":"A"},{"text":"Empty","value":"B"},{"text":"Either completely or partially filled","value":"C"},{"text":"None","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":9216,"question":"The electrons in the outermost shell are called","choices":[{"text":"Super electrons","value":"A"},{"text":"Valance electrons","value":"B"},{"text":"Full valance","value":"C"},{"text":"Upper deep up","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":9215,"question":"Conductivity of semiconductor is of order of","choices":[{"text":"10<sup>-6</sup> to 10<sup>4</sup>&nbsp;Ω<sup>-1</sup> m<sup>-1</sup>","value":"A"},{"text":"10<sup>-10</sup> to 10<sup>-20</sup> (Ωm)<sup>-1</sup>","value":"B"},{"text":"10<sup>7</sup> Ωm<sup>-1</sup>","value":"C"},{"text":"None","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":9214,"question":"Such substances which break soon after they cross elastic limit is called","choices":[{"text":"Weak substance","value":"A"},{"text":"Ductile substance","value":"B"},{"text":"Brittle substance","value":"C"},{"text":"Organic substance","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":9213,"question":"The SI unit of stress is same as that of","choices":[{"text":"Momentum","value":"A"},{"text":"Pressure","value":"B"},{"text":"Force","value":"C"},{"text":"Length","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":9212,"question":"The ability of body to return to its original shape is called","choices":[{"text":"Elasticity","value":"A"},{"text":"Stress","value":"B"},{"text":"Strain","value":"C"},{"text":"Shear","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":9211,"question":"Which one of the following is polymer","choices":[{"text":"Polythene","value":"A"},{"text":"Polystyrene","value":"B"},{"text":"Nylon","value":"C"},{"text":"All","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":9210,"question":"Amorphous solids are called","choices":[{"text":"Polymeric","value":"A"},{"text":"Crystal","value":"B"},{"text":"Glassy solids","value":"C"},{"text":"All","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":9209,"question":"The idea that all magnetic effects may be due to circulating currents (i.e moving charges) Was first held by","choices":[{"text":"Ampere","value":"A"},{"text":"Faraday","value":"B"},{"text":"Lenz","value":"C"},{"text":"Gauss","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":9208,"question":"When a germanium atom is doped with phosphorous atoms it becomes","choices":[{"text":"N-type semiconductor","value":"A"},{"text":"p-type semiconductor","value":"B"},{"text":"An insulator","value":"C"},{"text":"None of them","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":9207,"question":"Acceptor impurities donate","choices":[{"text":"Holes","value":"A"},{"text":"Electrons","value":"B"},{"text":"Both Electrons and Holes","value":"C"},{"text":"None of them","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":9206,"question":"Donor impurities donate","choices":[{"text":"Holes","value":"A"},{"text":"Electrons","value":"B"},{"text":"Both holes and electrons","value":"C"},{"text":"None of them","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":9205,"question":"An n-type semiconductor is obtained by doping germanium or silicon with","choices":[{"text":"Tetravalent impurity","value":"A"},{"text":"Trivalent impurity","value":"B"},{"text":"Pentavalent impurity","value":"C"},{"text":"Monovalent inpurity","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":9204,"question":"The charged nucleus of an atom itself spins its magnetic field is","choices":[{"text":"Equal to the field produced by orbital electrons","value":"A"},{"text":"Greater than the field produced by orbital electrons","value":"B"},{"text":"Much weaker than the field produced by orbital electrons","value":"C"},{"text":"Very strong","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":9203,"question":"The greatest stress that a material can endure without losing the proportionality between stress and strain is called","choices":[{"text":"Plasticity","value":"A"},{"text":"Breaking point","value":"B"},{"text":"Proportional limit","value":"C"},{"text":"Strain","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":9202,"question":"In the stress-strain graph stress is increased linearly with strain until a point is reached this point is known as","choices":[{"text":"Plastic limit","value":"A"},{"text":"Plastic deformation","value":"B"},{"text":"Proportional limit","value":"C"},{"text":"Elastic behaviour","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":9201,"question":"Ratio between total intensity of magnetic field at equator to poles is","choices":[{"text":"1 : 1","value":"A"},{"text":"2 : 1","value":"B"},{"text":"1 : 2","value":"C"},{"text":"1 : 4","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":9200,"question":"The conductivity of super conductor at critical temperature becomes","choices":[{"text":"Zero","value":"A"},{"text":"1","value":"B"},{"text":"Infinite","value":"C"},{"text":"Negative","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":9199,"question":"The unit cell of the shape of match box is called","choices":[{"text":"Cubic","value":"A"},{"text":"Tetragonal","value":"B"},{"text":"Orthorhombic","value":"C"},{"text":"Rhomboheral","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":9198,"question":"Which of the following is not true for a crystalline substance","choices":[{"text":"Shorter range order","value":"A"},{"text":"Isotropic electrical conductivity","value":"B"},{"text":"Flat surface","value":"C"},{"text":"Sharp melting point","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":9197,"question":"The young s modulus for a perfectly rigid body is","choices":[{"text":"Zero","value":"A"},{"text":"1","value":"B"},{"text":"Infinite","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":9196,"question":"A wire is stretched by applying a stretching force.If the stretching force is doubled within elastic limit Then energy stored in the wire will","choices":[{"text":"Be double","value":"A"},{"text":"Increase by four times","value":"B"},{"text":"Increase by eight time","value":"C"},{"text":"Remain same","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":9195,"question":"A women of 50 kg distributes her wright equally over high-heeld shoes. Each heel has an area of 0.75 cm<sup>2</sup>. The pressure exerted by each heel will be","choices":[{"text":"6.66 x 10<sup>6</sup> Pa","value":"A"},{"text":"3.33&nbsp;x 10<sup>6</sup>&nbsp;Pa","value":"B"},{"text":"1.67&nbsp;x 10<sup>6</sup>&nbsp;Pa","value":"C"},{"text":"3.33&nbsp;x 10<sup>-6</sup>&nbsp;Pa","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":9194,"question":"The limit up to which the stress is directly proportional to strain is called","choices":[{"text":"Elastic limit","value":"A"},{"text":"Proportional limit","value":"B"},{"text":"Breaking limit","value":"C"},{"text":"Ultimate tensile limit","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":9193,"question":"If the tensile force is suddenly removed from a wire then its temperature will","choices":[{"text":"Decrease","value":"A"},{"text":"Increase","value":"B"},{"text":"Becomes zero","value":"C"},{"text":"Remain constant","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":9192,"question":"In compound microscope image formed is","choices":[{"text":"Real erect and diminished","value":"A"},{"text":"Virtual inverted magnitude","value":"B"},{"text":"Real inverted and magnified","value":"C"},{"text":"Virtual inverted and magnified","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":9191,"question":"Spectrometer can be used to","choices":[{"text":"Measure wave length of light","value":"A"},{"text":"Measure refractive index of the materials","value":"B"},{"text":"Study spectra of light","value":"C"},{"text":"All","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":9190,"question":"Optical device used in spectrometer","choices":[{"text":"Simple microscope","value":"A"},{"text":"Compound microscope","value":"B"},{"text":"Telescope","value":"C"},{"text":"Any of them","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":9189,"question":"Basic principle of an optical fibre is","choices":[{"text":"Reflection","value":"A"},{"text":"Scattering","value":"B"},{"text":"Polarization","value":"C"},{"text":"Total internal reflection","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":9188,"question":"The index of refraction of diamond is 2.0 velocity of light in diamond in m/s is","choices":[{"text":"6 x 10<sup>8</sup>","value":"A"},{"text":"3 x 10<sup>8</sup>","value":"B"},{"text":"2 x 10<sup>8</sup>","value":"C"},{"text":"1.5 x 10<sup>8</sup>","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":9187,"question":"The cause of power loss in optic fibre is","choices":[{"text":"Absorption","value":"A"},{"text":"Scattering","value":"B"},{"text":"Dispersion","value":"C"},{"text":"All","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":9186,"question":"Source of light used in the fibre optic communication","choices":[{"text":"Led","value":"A"},{"text":"Laser","value":"B"},{"text":"Photo diode","value":"C"},{"text":"Both a and b","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":9185,"question":"An object is placed at a distance of 200 cm from a convex lens of focal length 10 cm the linear magnification is","choices":[{"text":"1/3","value":"A"},{"text":"2/3","value":"B"},{"text":"3/4","value":"C"},{"text":"None","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":9184,"question":"In compound microscope magnification of objective is 2 and magnification of eyepiece is 4 magnification of compound microscope is","choices":[{"text":"2","value":"A"},{"text":"6","value":"B"},{"text":"8","value":"C"},{"text":"None","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":9183,"question":"A telescope has an objective of focal length 10 cm the magnifying power of telescope is 5.Its length in normal adjustment is","choices":[{"text":"7.5cm","value":"A"},{"text":"10.5 cm","value":"B"},{"text":"12 cm","value":"C"},{"text":"15 cm","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":9182,"question":"A convex lens of focal length 5 cm is used as magnifying glass Its magnifying power when the image is formed at infinity","choices":[{"text":"6","value":"A"},{"text":"5","value":"B"},{"text":"1.5","value":"C"},{"text":"7","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":9181,"question":"Which does not show polarization","choices":[{"text":"Longitudinal wave in gas","value":"A"},{"text":"Transverse wave in gas","value":"B"},{"text":"Both a and b","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":9180,"question":"Which of the following is conserved when light waves interfere","choices":[{"text":"Intensity","value":"A"},{"text":"Energy","value":"B"},{"text":"Amplitude","value":"C"},{"text":"Momentum","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":9179,"question":"Inverse square law for luminace is valid for","choices":[{"text":"Search light","value":"A"},{"text":"Isotropic point source","value":"B"},{"text":"Cylindrical source","value":"C"},{"text":"All types of source","value":"D"},{"value":"E"}],"correctAnswer":2}]