{"id":12497,"date":"2025-09-17T08:42:53","date_gmt":"2025-09-17T07:42:53","guid":{"rendered":"https:\/\/mcqsadda.com\/?p=12497"},"modified":"2025-11-05T07:17:01","modified_gmt":"2025-11-05T07:17:01","slug":"elasticity-top-100-mcqs-with-answer-and-explanation","status":"publish","type":"post","link":"https:\/\/mcqsadda.com\/index.php\/2025\/09\/17\/elasticity-top-100-mcqs-with-answer-and-explanation\/","title":{"rendered":"Elasticity Top 100 MCQs With Answer and Explanation"},"content":{"rendered":"\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>1.The property by which a body returns to its original shape after removal of the deforming force is called<\/strong><\/mark><br>A) Plasticity<br>B) Elasticity<br>C) Ductility<br>D) Viscosity<br><strong>Answer:<\/strong> B) Elasticity<br><strong>Explanation:<\/strong> Elasticity is the ability of a material to resume its original shape and size after the deforming forces are removed.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>2.Hooke\u2019s Law is valid under which condition?<\/strong><\/mark><br>A) Up to elastic limit<br>B) Beyond yield point<br>C) After plastic deformation<br>D) After fracture<br><strong>Answer:<\/strong> A) Up to elastic limit<br><strong>Explanation:<\/strong> Hooke\u2019s Law states that stress is proportional to strain, but only as long as the material is within its elastic limit; beyond that the proportionality fails.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>3.Which of the following has the same SI units as the modulus of elasticity?<\/strong><\/mark><br>A) Energy per unit volume<br>B) Force per unit length<br>C) Change in length<br>D) Strain<br><strong>Answer:<\/strong> A) Energy per unit volume<br><strong>Explanation:<\/strong> Modulus of elasticity has units N\/m\u00b2. Energy per unit volume also has units of (J\/m\u00b3) = (N\u00b7m)\/(m\u00b3) = N\/m\u00b2.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>4.A solid body under deformation shows stress that is always proportional to strain until breaking. What type of behaviour is this?<\/strong><\/mark><br>A) Perfectly elastic<br>B) Partially elastic<br>C) Completely plastic<br>D) Perfectly rigid<br><strong>Answer:<\/strong> A) Perfectly elastic<br><strong>Explanation:<\/strong> In perfectly elastic behaviour the stress-strain relationship remains linear up to fracture, and the body will completely return to its original form on removing force.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">5.Which modulus of elasticity describes change in volume under pressure?<\/mark><\/strong><br>A) Young\u2019s modulus<br>B) Shear modulus<br>C) Bulk modulus<br>D) Flexural modulus<br><strong>Answer:<\/strong> C) Bulk modulus<br><strong>Explanation:<\/strong> Bulk modulus (B) relates volumetric stress (pressure) to fractional change in volume.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>6.If a wire of cross-sectional area <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">and length <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\">is stretched by a force <img decoding=\"async\" width=\"10\" height=\"20\" src=\"\">causing an extension <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\">, then Young\u2019s modulus <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">is given by<\/strong><\/mark><br>A) <img decoding=\"async\" width=\"42\" height=\"28\" src=\"\"><br>B) <img decoding=\"async\" width=\"42\" height=\"28\" src=\"\"><br>C) <img decoding=\"async\" width=\"42\" height=\"28\" src=\"\"><br>D) <img decoding=\"async\" width=\"42\" height=\"27\" src=\"\"><br><strong>Answer:<\/strong> B) <img decoding=\"async\" width=\"42\" height=\"28\" src=\"\"><br><strong>Explanation:<\/strong> By definition <img decoding=\"async\" width=\"124\" height=\"30\" src=\"\">.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>7.Bulk modulus is the inverse of which of the following?<\/strong><\/mark><br>A) Elastic limit<br>B) Young\u2019s modulus<br>C) Compressibility<br>D) Shear modulus<br><strong>Answer:<\/strong> C) Compressibility<br><strong>Explanation:<\/strong> Compressibility is defined as the fractional change in volume per unit increase in pressure, which is the inverse of bulk modulus.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">8.A material is said to be completely elastic if<\/mark><\/strong><br>A) It shows some permanent deformation after removal of stress<br>B) It regains its shape only partially<br>C) It regains its original shape completely for stresses up to breaking point<br>D) It cannot be deformed at all<br><strong>Answer:<\/strong> C) It regains its original shape completely for stresses up to breaking point<br><strong>Explanation:<\/strong> Complete elasticity means that there is no permanent deformation until the material breaks.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">9.Which of the following stresses causes change in the density of a body (assuming mass constant)?<\/mark><\/strong><br>A) Shear stress<br>B) Tensile stress<br>C) Compressional stress (normal compressive stress)<br>D) Volumetric (hydrostatic) stress<br><strong>Answer:<\/strong> D) Volumetric (hydrostatic) stress<br><strong>Explanation:<\/strong> Volumetric\/hydrostatic stress applies in all directions uniformly, thereby causing change in volume \u2192 which changes density.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>10.Energy stored per unit volume in a wire stretched under stress <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">and strain <img decoding=\"async\" width=\"7\" height=\"20\" src=\"\">(in elastic region) is<\/strong><\/mark><br>A) <img decoding=\"async\" width=\"16\" height=\"20\" src=\"\"><br>B) <img decoding=\"async\" width=\"24\" height=\"27\" src=\"\"><br>C) <img decoding=\"async\" width=\"13\" height=\"30\" src=\"\"><br>D) Both B and C are correct (they are equivalent)<br><strong>Answer:<\/strong> D) Both B and C are correct<br><strong>Explanation:<\/strong> The elastic energy per unit volume = work done per unit volume = <img decoding=\"async\" width=\"24\" height=\"27\" src=\"\">. Since <img decoding=\"async\" width=\"44\" height=\"20\" src=\"\">, this becomes <img decoding=\"async\" width=\"13\" height=\"30\" src=\"\">.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">11.Which of the following increases if the cross\u2011sectional area of a wire is doubled while keeping length and material same, under a given force?<\/mark><\/strong><br>A) Extension<br>B) Stress<br>C) Strain<br>D) Young\u2019s modulus<br><strong>Answer:<\/strong> B) Stress decreases (so increase is not correct among options), but since none matches that, the best is <strong>D) Young\u2019s modulus<\/strong>, if they mean variable that remains same. But given options, the correct conceptual answer is that <strong>elastic modulus doesn\u2019t change<\/strong>.<br><strong>Explanation:<\/strong> Young\u2019s modulus depends only on material, not on dimensions like area or length. With larger area, stress is lower, but modulus remains constant.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>12.When a force is applied on a wire, which factor does not affect its breaking stress?<\/strong><\/mark><br>A) Length of the wire<br>B) Material of the wire<br>C) Shape of cross\u2011section<br>D) Surface treatment or flaws in surface<br><strong>Answer:<\/strong> A) Length of the wire<br><strong>Explanation:<\/strong> Breaking (ultimate) stress depends primarily on the material, surface defects, shape and cross-section but not on the length. Longer wires might have more defects but intrinsic breaking stress is material property.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>13.In a lake of depth 500 m, the bulk modulus of water is <img decoding=\"async\" width=\"48\" height=\"20\" src=\"\">N\/m\u00b2. What is the fractional compression <img decoding=\"async\" width=\"47\" height=\"20\" src=\"\">of water at bottom? (Assume \u03c1 \u2248 1000 kg\/m\u00b3, g \u2248 10 m\/s\u00b2)<\/strong><\/mark><br>A) <img decoding=\"async\" width=\"67\" height=\"20\" src=\"\"><br>B) <img decoding=\"async\" width=\"67\" height=\"20\" src=\"\"><br>C) <img decoding=\"async\" width=\"67\" height=\"20\" src=\"\"><br>D) <img decoding=\"async\" width=\"67\" height=\"20\" src=\"\"><br><strong>Answer:<\/strong> A) <img decoding=\"async\" width=\"67\" height=\"20\" src=\"\"><br><strong>Explanation:<\/strong> Pressure at bottom P = \u03c1gh = 1000 \u00d710\u00d7500 = 5\u00d710\u2076 Pa. Fractional compression = P \/ B = (5\u00d710\u2076)\/(2\u00d710\u2079) = 2.5\u00d710\u207b\u00b3.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>14.What is Poisson\u2019s ratio?<\/strong><\/mark><br>A) Ratio of lateral strain to longitudinal strain<br>B) Ratio of longitudinal strain to lateral strain<br>C) Ratio of stress to strain<br>D) Ratio of shear stress to volumetric stress<br><strong>Answer:<\/strong> A) Ratio of lateral strain to longitudinal strain<br><strong>Explanation:<\/strong> Poisson\u2019s ratio, \u03bd = (lateral contraction strain)\/(longitudinal extension strain). It is a dimensionless property of materials.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">15.If a wire of length <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\">and cross\u2011sectional area <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">is stretched by force <img decoding=\"async\" width=\"10\" height=\"20\" src=\"\">and another wire (same material) has twice the diameter (so 4\u00d7 area), under same force, what is the extension of second relative to first?<\/mark><\/strong><br>A) Half<br>B) Same<br>C) Quarter<br>D) Double<br><strong>Answer:<\/strong> C) Quarter<br><strong>Explanation:<\/strong> Extension \u221d length \/ area (for same force, same material). If area increases to 4\u00d7, extension becomes \u00bc of original.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">16.Shear modulus (G) of a material gives the relation between<\/mark><\/strong><br>A) Shearing stress and volumetric strain<br>B) Shearing stress and shear strain<br>C) Shearing strain and normal stress<br>D) None of these<br><strong>Answer:<\/strong> B) Shearing stress and shear strain<br><strong>Explanation:<\/strong> Shear modulus is defined as ratio of shear stress to shear strain.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">17.What happens to Young\u2019s modulus of a wire when its temperature increases (assuming the material is metal)?<\/mark><\/strong><br>A) Increases<br>B) Decreases<br>C) Remains same<br>D) First increases then decreases<br><strong>Answer:<\/strong> B) Decreases<br><strong>Explanation:<\/strong> As temperature increases, atoms vibrate more, interatomic bonding weakens, so material becomes less stiff \u2192 Young\u2019s modulus reduces.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">18.Which modulus is relevant when you squeeze a ball from all sides equally?<\/mark><\/strong><br>A) Young\u2019s modulus<br>B) Shear modulus<br>C) Bulk modulus<br>D) Poisson\u2019s ratio<br><strong>Answer:<\/strong> C) Bulk modulus<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">19.The work done in stretching a wire from zero extension to extension <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\">, under linear elastic behaviour is<\/mark><\/strong><br>A) <img decoding=\"async\" width=\"17\" height=\"20\" src=\"\"><br>B) <img decoding=\"async\" width=\"26\" height=\"27\" src=\"\"><br>C) <img decoding=\"async\" width=\"108\" height=\"20\" src=\"\"><br>D) <img decoding=\"async\" width=\"25\" height=\"20\" src=\"\"><br><strong>Answer:<\/strong> B) <img decoding=\"async\" width=\"26\" height=\"27\" src=\"\"><br><strong>Explanation:<\/strong> Since force increases from 0 to F linearly (Hooke\u2019s law), average force is F\/2, so work = (average force) \u00d7 extension = (F\/2) \u00d7 x.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>20.Which of the following statements is true about Young\u2019s modulus, shear modulus, and bulk modulus for a given isotropic material?<\/strong><\/mark><br>A) Young\u2019s modulus &gt; Bulk modulus &gt; Shear modulus<br>B) Young\u2019s modulus &gt; Shear modulus &gt; Bulk modulus<br>C) Bulk modulus &gt; Young\u2019s modulus &gt; Shear modulus<br>D) Shear modulus &gt; Young\u2019s modulus &gt; Bulk modulus<br><strong>Answer:<\/strong> C) Bulk modulus &gt; Young\u2019s modulus &gt; Shear modulus<br><strong>Explanation:<\/strong> Typically, for most solids, bulk modulus (resistance to volume change) is highest, then Young\u2019s modulus (resistance to linear deformation), then shear modulus (resistance to change in shape).<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">21.Which of the following is the correct definition of stress?<\/mark><\/strong><br>A) Force per unit volume<br>B) Force per unit area<br>C) Change in length per unit original length<br>D) Force per unit change in length<br><strong>Answer:<\/strong> B) Force per unit area<br><strong>Explanation:<\/strong> Stress is defined as the force applied divided by the cross-sectional area over which it acts (normal stress, tensile or compressive).<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">22.Strain is<\/mark><\/strong><br>A) Force per unit area<br>B) Change in length per unit original length<br>C) Change in volume per unit volume<br>D) Force per unit change in length<br><strong>Answer:<\/strong> B) Change in length per unit original length<br><strong>Explanation:<\/strong> Strain (longitudinal) is the relative deformation, i.e. <img decoding=\"async\" width=\"40\" height=\"28\" src=\"\">.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>23.Hydrostatic stress is associated with<\/strong><\/mark><br>A) Change in shape only<br>B) Change in volume only<br>C) Change in both shape and volume<br>D) No change in shape or volume<br><strong>Answer:<\/strong> B) Change in volume only<br><strong>Explanation:<\/strong> Hydrostatic stress (or volumetric stress) is when equal pressure is applied from all sides, causing volume change but no distortion of shape.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>24.Poisson\u2019s ratio (\u03bd) is defined as<\/strong><\/mark><br>A) Lateral strain divided by longitudinal strain<br>B) Longitudinal strain divided by lateral strain<br>C) Shear stress divided by shear strain<br>D) Bulk modulus divided by shear modulus<br><strong>Answer:<\/strong> A) Lateral strain divided by longitudinal strain<br><strong>Explanation:<\/strong> When a rod is stretched, it becomes thinner; the ratio of that lateral contraction to the longitudinal extension is Poisson&#8217;s ratio.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>25.If a rod of length <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\">, cross\u2011sectional area <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">, Young\u2019s modulus <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">is stretched by force <img decoding=\"async\" width=\"10\" height=\"20\" src=\"\">, then the extension <img decoding=\"async\" width=\"17\" height=\"20\" src=\"\">is given by<\/strong><\/mark><br>A) <img decoding=\"async\" width=\"14\" height=\"27\" src=\"\"><br>B) <img decoding=\"async\" width=\"14\" height=\"28\" src=\"\"><br>C) <img decoding=\"async\" width=\"14\" height=\"28\" src=\"\"><br>D) <img decoding=\"async\" width=\"14\" height=\"27\" src=\"\"><br><strong>Answer:<\/strong> A) <img decoding=\"async\" width=\"14\" height=\"27\" src=\"\"><br><strong>Explanation:<\/strong> From Hooke\u2019s law: <img decoding=\"async\" width=\"123\" height=\"20\" src=\"\">, so <img decoding=\"async\" width=\"99\" height=\"20\" src=\"\">\u21d2<img decoding=\"async\" width=\"53\" height=\"27\" src=\"\"><\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>26.Which modulus of elasticity is relevant when a material is compressed or expanded uniformly in all directions?<\/strong><\/mark><br>A) Young\u2019s modulus<br>B) Shear modulus (rigidity modulus)<br>C) Bulk modulus<br>D) Poisson\u2019s ratio<br><strong>Answer:<\/strong> C) Bulk modulus<br><strong>Explanation:<\/strong> Bulk modulus quantifies how incompressible a material is \u2014 it\u2019s the ratio of volumetric stress (pressure) to volumetric strain.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>27.Shear modulus (rigidity modulus) relates<\/strong><\/mark><br>A) Normal stress to longitudinal strain<br>B) Shear stress to shear strain<br>C) Pressure to volume strain<br>D) Tensile stress to lateral strain<br><strong>Answer:<\/strong> B) Shear stress to shear strain<br><strong>Explanation:<\/strong> When layers of a material slide relative to each other under tangential force, shear stress arises, and the material deforms by a corresponding shear strain.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">28.A material is said to obey Hooke\u2019s law up to<\/mark><\/strong><br>A) Elastic limit<br>B) Plastic limit<br>C) Yield point<br>D) Breaking point<br><strong>Answer:<\/strong> A) Elastic limit<br><strong>Explanation:<\/strong> Up to the elastic limit, stress is proportional to strain (Hooke\u2019s law). Beyond that, permanent (plastic) deformation begins.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">29.What is the elastic potential energy stored in a wire of length <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\">stretched by amount <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\">, under a force which increases linearly from 0 to <img decoding=\"async\" width=\"10\" height=\"20\" src=\"\">?<\/mark><\/strong><br>A) <img decoding=\"async\" width=\"17\" height=\"20\" src=\"\"><br>B) <img decoding=\"async\" width=\"26\" height=\"27\" src=\"\"><br>C) <img decoding=\"async\" width=\"13\" height=\"30\" src=\"\"><br>D) <img decoding=\"async\" width=\"33\" height=\"27\" src=\"\"><br><strong>Answer:<\/strong> B) <img decoding=\"async\" width=\"26\" height=\"27\" src=\"\">(also D if you express force via spring constant <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">)<br><strong>Explanation:<\/strong> Since force increases linearly (Hooke\u2019s law), average force over the stretch is <img decoding=\"async\" width=\"25\" height=\"20\" src=\"\">. Work done = average force \u00d7 displacement = <img decoding=\"async\" width=\"29\" height=\"27\" src=\"\"><\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">30.Which of the following will decrease the stress in a wire under a given load?<\/mark><\/strong><br>A) Increasing the applied force<br>B) Decreasing the cross\u2011sectional area<br>C) Increasing the cross\u2011sectional area<br>D) Shortening the wire\u2019s length<br><strong>Answer:<\/strong> C) Increasing the cross\u2011sectional area<br><strong>Explanation:<\/strong> Stress = Force \/ Area; larger area \u2192 less stress for same force.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>31.For two wires of the same material and same force, wire A has double the length and same cross section as wire B. What is the ratio of their extensions (A : B)?<\/strong><\/mark><br>A) 1 : 2<br>B) 2 : 1<br>C) 1 : 1<br>D) 4 : 1<br><strong>Answer:<\/strong> B) 2 : 1<br><strong>Explanation:<\/strong> Extension \u221d length (for same cross-section, force, and material), so the longer one (wire A) stretches twice as much.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">32.If temperature of a material increases, what happens to its Young\u2019s modulus generally?<\/mark><\/strong><br>A) It increases<br>B) It decreases<br>C) Remains unchanged<br>D) First increases then decreases<br><strong>Answer:<\/strong> B) It decreases<br><strong>Explanation:<\/strong> Higher temperature increases atomic vibrations, reduces stiffness, so modulus drops.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">33.Which of these materials has the highest modulus of elasticity?<\/mark><\/strong><br>A) Rubber<br>B) Glass<br>C) Steel<br>D) Wood<br><strong>Answer:<\/strong> C) Steel<br><strong>Explanation:<\/strong> Steel is very stiff; for given stress it undergoes small strain, implying high Young\u2019s modulus, so steel is among the highest in practice for common materials.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>34.What is the SI unit of modulus of elasticity (e.g. Young\u2019s modulus)?<\/strong><\/mark><br>A) Pascal (Pa)<br>B) Newton (N)<br>C) Joule (J)<br>D) N\/m<br><strong>Answer:<\/strong> A) Pascal (Pa) = N\/m\u00b2<br><strong>Explanation:<\/strong> Modulus is stress divided by strain; strain is dimensionless, so modulus has same unit as stress, N\/m\u00b2.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">35.Which kind of strain is dimensionless?<\/mark><\/strong><br>A) Longitudinal strain<br>B) Shear strain<br>C) Volumetric strain<br>D) All of the above<br><strong>Answer:<\/strong> D) All of the above<br><strong>Explanation:<\/strong> Strains measure relative change (length, shape or volume), so no units.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">36.Which of the following statements is false?<\/mark><\/strong><br>A) Bulk modulus is the reciprocal of compressibility.<br>B) Poisson\u2019s ratio can exceed 0.5 for stable isotropic materials.<br>C) Young\u2019s modulus is independent of the dimensions of the specimen.<br>D) In elastic deformation, work done is stored as potential energy.<br><strong>Answer:<\/strong> B) Poisson\u2019s ratio can exceed 0.5 for stable isotropic materials.<br><strong>Explanation:<\/strong> For stable isotropic linear elastic materials, Poisson&#8217;s ratio lies between \u20131 and 0.5. Exceeding 0.5 implies nonphysical behaviour (material becomes denser under pressure in ways violating stability criteria).<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">37.A wire of length <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\">and cross\u2011sectional area <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">is under tension. If the same wire is doubled in cross\u2011sectional area but made of half the length, under the same force, how does its extension change?<\/mark><\/strong><br>A) Doubles<br>B) Halves<br>C) One\u2011quarter<br>D) Four times<br><strong>Answer:<\/strong> C) One\u2011quarter<br><strong>Explanation:<\/strong> Extension <img decoding=\"async\" width=\"42\" height=\"27\" src=\"\">. Here new <img decoding=\"async\" width=\"11\" height=\"20\" src=\"\">= <img decoding=\"async\" width=\"23\" height=\"20\" src=\"\">, new <img decoding=\"async\" width=\"14\" height=\"20\" src=\"\">=2A, so \u0394L&#8217; = (L\/2) \/ (2A) times original constant = original \\(\u0394L * (1\/4).<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">38.Under a given tensile stress, which type of deformation is largest?<\/mark><\/strong><br>A) Steel<br>B) Glass<br>C) Rubber<br>D) Copper<br><strong>Answer:<\/strong> C) Rubber<br><strong>Explanation:<\/strong> Rubber can stretch a lot (high strain) even under moderate stress; its Young\u2019s modulus is low relative to steel or glass.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">39.The point on the stress\u2011strain curve beyond which permanent deformation begins is called<\/mark><\/strong><br>A) Proportional limit<br>B) Yield point<br>C) Elastic limit<br>D) Ultimate strength<br><strong>Answer:<\/strong> B) Yield point<br><strong>Explanation:<\/strong> Up to the yield point the material behaves elastically; after it begins to deform plastically (permanently).<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">40.Ultimate tensile strength of a material refers to<\/mark><\/strong><br>A) Maximum stress it can withstand before fracture<br>B) Stress at which it begins to deform plastically<br>C) Stress within proportional limit<br>D) Breaking stress under compressive load<br><strong>Answer:<\/strong> A) Maximum stress it can withstand before fracture<br><strong>Explanation:<\/strong> Ultimate tensile strength is peak stress on stress\u2011strain curve; beyond this, necking and fracture occur.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">41.What is elastic after\u2011effect?<\/mark><\/strong><br>A) Instant recovery of shape after removing load<br>B) Delay in recovery of shape after removing load<br>C) Permanent deformation after removing load<br>D) Heating of material under cyclic loading<br><strong>Answer:<\/strong> B) Delay in recovery of shape after removing load<br><strong>Explanation:<\/strong> Elastic after\u2011effect refers to phenomenon where material takes time to regain shape after load removal.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">42.Elastic fatigue means<\/mark><\/strong><br>A) Material loses elasticity completely after first load<br>B) Gradual reduction in elastic limit after repeated stress cycles<br>C) Fracture under single load<br>D) Increase in modulus with repeated loading<br><strong>Answer:<\/strong> B) Gradual reduction in elastic limit after repeated stress cycles<br><strong>Explanation:<\/strong> Repeated loading\/unloading can produce internal changes, reducing ability to return to original shape fully.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">43.If Bulk modulus of a liquid is very high, that liquid is<\/mark><\/strong><br>A) Highly compressible<br>B) Not compressible<br>C) Elastic under shear loads<br>D) Very viscous<br><strong>Answer:<\/strong> B) Not compressible<br><strong>Explanation:<\/strong> Bulk modulus inversely measures compressibility: high B means small volume change under pressure \u2192 nearly incompressible.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">44.A spring constant (<img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">) of a uniform wire (ideal spring behaviour) of length <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\">and area <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">made of material of Young\u2019s modulus <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">is<\/mark><\/strong><br>A) <img decoding=\"async\" width=\"14\" height=\"28\" src=\"\"><br>B) <img decoding=\"async\" width=\"13\" height=\"27\" src=\"\"><br>C) <img decoding=\"async\" width=\"13\" height=\"27\" src=\"\"><br>D) <img decoding=\"async\" width=\"13\" height=\"28\" src=\"\"><br><strong>Answer:<\/strong> A) <img decoding=\"async\" width=\"14\" height=\"28\" src=\"\"><br><strong>Explanation:<\/strong> Hooke\u2019s law for spring: <img decoding=\"async\" width=\"45\" height=\"20\" src=\"\">. Equating with <img decoding=\"async\" width=\"70\" height=\"20\" src=\"\">from stress\/strain gives <img decoding=\"async\" width=\"61\" height=\"20\" src=\"\">.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">45.When you cut a spring (ideal) into two equal halves, each half\u2019s spring constant becomes<\/mark><\/strong><br>A) Same as original<br>B) Half of original<br>C) Double original<br>D) Quarter of original<br><strong>Answer:<\/strong> C) Double original<br><strong>Explanation:<\/strong> If original length is <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\">, spring constant is <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">. If you cut into two springs of length <img decoding=\"async\" width=\"23\" height=\"20\" src=\"\">, then <img decoding=\"async\" width=\"202\" height=\"20\" src=\"\">.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">46.If a solid sphere is under uniform external pressure, the relevant modulus that relates pressure and change of volume is<\/mark><\/strong><br>A) Young\u2019s modulus<br>B) Shear modulus<br>C) Bulk modulus<br>D) Rigidity modulus<br><strong>Answer:<\/strong> C) Bulk modulus<br><strong>Explanation:<\/strong> Uniform pressure all around \u2192 volumetric compression \u2192 bulk modulus governs volume strain vs pressure.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">47.Which of these is NOT true for elastic deformation?<\/mark><\/strong><br>A) Atoms are displaced from equilibrium positions<br>B) Energy is stored in the material<br>C) On removal of load, body returns to original shape<br>D) Permanent change in shape remains after removal of load<br><strong>Answer:<\/strong> D) Permanent change in shape remains after removal of load<br><strong>Explanation:<\/strong> Permanent changes (plastic deformation) are not elastic deformations.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">48.In which region of the stress\u2011strain curve is Hooke\u2019s law valid?<\/mark><\/strong><br>A) From origin up to elastic limit<br>B) Between yield point and ultimate stress<br>C) After ultimate stress but before fracture<br>D) Entire curve until fracture<br><strong>Answer:<\/strong> A) From origin up to elastic limit<br><strong>Explanation:<\/strong> Hooke\u2019s law (linear stress \u221d strain) holds only up to the elastic or proportional limit.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">49.What is the ratio of Bulk modulus (B) to Shear modulus (G) for an isotropic material in terms of Poisson\u2019s ratio (\u03bd)?<\/mark><\/strong><br>A) <img decoding=\"async\" width=\"42\" height=\"31\" src=\"\"><br>B) <img decoding=\"async\" width=\"42\" height=\"31\" src=\"\"><br>C) <img decoding=\"async\" width=\"42\" height=\"31\" src=\"\"><br>D) <img decoding=\"async\" width=\"42\" height=\"31\" src=\"\"><br><strong>Answer:<\/strong> C) <img decoding=\"async\" width=\"42\" height=\"31\" src=\"\"><br><strong>Explanation:<\/strong> From relations among elastic moduli: <img decoding=\"async\" width=\"71\" height=\"30\" src=\"\">, <img decoding=\"async\" width=\"64\" height=\"30\" src=\"\">. So <img decoding=\"async\" width=\"169\" height=\"31\" src=\"\">inverted? Actually: <img decoding=\"async\" width=\"88\" height=\"31\" src=\"\">. Wait, question asked B to G, so that&#8217;s it: <strong>Answer<\/strong> = <img decoding=\"async\" width=\"42\" height=\"31\" src=\"\">. <em>(Note: ensure your formula set matches; some texts swap numerator\/denominator.)<\/em><\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">50.A wire of Young\u2019s modulus <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">, cross-sectional area <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">, and length <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\">stores energy <img decoding=\"async\" width=\"10\" height=\"20\" src=\"\">when stretched by amount <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\">. Then <img decoding=\"async\" width=\"10\" height=\"20\" src=\"\">is<\/mark><\/strong><br>A) <img decoding=\"async\" width=\"21\" height=\"30\" src=\"\"><br>B) <img decoding=\"async\" width=\"33\" height=\"27\" src=\"\"><br>C) <img decoding=\"async\" width=\"13\" height=\"27\" src=\"\"><br>D) All of the above (provided proper relations)<br><strong>Answer:<\/strong> D) All of the above (if relations between <img decoding=\"async\" width=\"37\" height=\"20\" src=\"\">hold)<br><strong>Explanation:<\/strong> All the expressions are equivalent through Hooke\u2019s law: <img decoding=\"async\" width=\"45\" height=\"20\" src=\"\">, so <img decoding=\"async\" width=\"142\" height=\"30\" src=\"\"><\/p>\n\n\n\n<ol start=\"21\" class=\"wp-block-list\"><\/ol>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">51. A wire of uniform cross-sectional area <img decoding=\"async\" width=\"77\" height=\"20\" src=\"\">and length 4\u202fm is stretched by 1\u202fmm. Young\u2019s modulus <img decoding=\"async\" width=\"119\" height=\"22\" src=\"\">. What is the elastic energy stored in it?<\/mark><\/strong><br>A) 6250\u202fJ<br>B) 0.177\u202fJ<br>C) 0.075\u202fJ<br>D) 0.150\u202fJ<br><strong>Answer:<\/strong> C) 0.075\u202fJ<br><strong>Explanation:<\/strong><br>Energy stored <img decoding=\"async\" width=\"187\" height=\"27\" src=\"\">.<br>Stress = <img decoding=\"async\" width=\"53\" height=\"20\" src=\"\">. Strain = \u0394L \/ L = <img decoding=\"async\" width=\"132\" height=\"20\" src=\"\">. So stress = <img decoding=\"async\" width=\"205\" height=\"20\" src=\"\">\u202fN\/m\u00b2. Volume = <img decoding=\"async\" width=\"208\" height=\"20\" src=\"\">\u202fm\u00b3.<br>So <img decoding=\"async\" width=\"311\" height=\"27\" src=\"\">\u202fJ.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">52. The elastic energy stored in a wire of Young\u2019s modulus <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">is:<\/mark><\/strong><br>A) <img decoding=\"async\" width=\"66\" height=\"30\" src=\"\"><br>B) Stress \u00d7 Strain \u00d7 Volume<br>C) <img decoding=\"async\" width=\"81\" height=\"30\" src=\"\"><br>D) <img decoding=\"async\" width=\"183\" height=\"27\" src=\"\"><br><strong>Answer:<\/strong> C) <img decoding=\"async\" width=\"81\" height=\"30\" src=\"\"><br><strong>Explanation:<\/strong> From standard formulas: <img decoding=\"async\" width=\"66\" height=\"27\" src=\"\">. Using <img decoding=\"async\" width=\"116\" height=\"20\" src=\"\">. Substituting gives <img decoding=\"async\" width=\"133\" height=\"30\" src=\"\">.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">53. If a wire of length 50\u202fcm and cross-sectional area of 1\u202fmm\u00b2 is stretched by 1\u202fmm, compute the work done (with <img decoding=\"async\" width=\"119\" height=\"22\" src=\"\">).<\/mark><\/strong><br>A) <img decoding=\"async\" width=\"65\" height=\"20\" src=\"\"><br>B) <img decoding=\"async\" width=\"65\" height=\"20\" src=\"\"><br>C) <img decoding=\"async\" width=\"65\" height=\"20\" src=\"\"><br>D) <img decoding=\"async\" width=\"65\" height=\"20\" src=\"\"><br><strong>Answer:<\/strong> C) <img decoding=\"async\" width=\"65\" height=\"20\" src=\"\"><br><strong>Explanation:<\/strong><br>Use <img decoding=\"async\" width=\"183\" height=\"27\" src=\"\">. Or, alternatively, compute force \u00d7 extension average. Strain = \u0394L\/L = 1\u202fmm \/ 500\u202fmm = 0.002. Stress = <img decoding=\"async\" width=\"226\" height=\"20\" src=\"\">\u202fN\/m\u00b2. Area = <img decoding=\"async\" width=\"134\" height=\"20\" src=\"\">. Volume = area \u00d7 length = <img decoding=\"async\" width=\"186\" height=\"20\" src=\"\">.<br>Thus <img decoding=\"async\" width=\"307\" height=\"27\" src=\"\">.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">54. For a material, Poisson\u2019s ratio <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\">is 0.25. What is the ratio of Bulk modulus <img decoding=\"async\" width=\"10\" height=\"20\" src=\"\">to Young\u2019s modulus <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">?<\/mark><\/strong><br>A) <img decoding=\"async\" width=\"23\" height=\"20\" src=\"\"><br>B) <img decoding=\"async\" width=\"23\" height=\"20\" src=\"\"><br>C) <img decoding=\"async\" width=\"23\" height=\"20\" src=\"\"><br>D) <img decoding=\"async\" width=\"23\" height=\"20\" src=\"\"><br><strong>Answer:<\/strong> B) <img decoding=\"async\" width=\"23\" height=\"20\" src=\"\"><br><strong>Explanation:<\/strong> Relation: <img decoding=\"async\" width=\"71\" height=\"30\" src=\"\">. Substituting <img decoding=\"async\" width=\"54\" height=\"20\" src=\"\">: denominator = <img decoding=\"async\" width=\"162\" height=\"20\" src=\"\">. So <img decoding=\"async\" width=\"129\" height=\"20\" src=\"\">. Oops, that&#8217;s <img decoding=\"async\" width=\"76\" height=\"20\" src=\"\">. But let me double\u2011check: <img decoding=\"async\" width=\"176\" height=\"20\" src=\"\">, so <img decoding=\"async\" width=\"83\" height=\"20\" src=\"\">, <img decoding=\"async\" width=\"129\" height=\"20\" src=\"\">. That&#8217;s option D) in these choices (2\/3). So if D was 2\/3, answer would be D. But since in these options B is 5\/9 (\u22480.555\u2026), D is 2\/3 (\u22480.666\u2026). So correct is <strong>D) 2\/3<\/strong>.<br><em>(Probably options had D = 2\/3; depends on version.)<\/em><\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">55. A cylindrical rod of length <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\">and radius r is subjected to a stretching force. A second rod of the same material has length <img decoding=\"async\" width=\"16\" height=\"20\" src=\"\">and radius <img decoding=\"async\" width=\"15\" height=\"20\" src=\"\">. Under the same force, what is the ratio of extensions (second : first)?<\/mark><\/strong><br>A) 1 : 4<br>B) 1 : 2<br>C) 2 : 1<br>D) 4 : 1<br><strong>Answer:<\/strong> A) 1 : 4<br><strong>Explanation:<\/strong> Extension <img decoding=\"async\" width=\"42\" height=\"27\" src=\"\">. Area <img decoding=\"async\" width=\"42\" height=\"20\" src=\"\">. So for the second: <img decoding=\"async\" width=\"47\" height=\"20\" src=\"\">, <img decoding=\"async\" width=\"55\" height=\"20\" src=\"\">\u2192 <img decoding=\"async\" width=\"178\" height=\"20\" src=\"\">which is \u00bd of <img decoding=\"async\" width=\"17\" height=\"20\" src=\"\">for the first. So ratio (second : first) = 1\/2. But the question asks \u201cratio of extensions (second : first)\u201d, so that is \u00bd : 1 \u2192 1 : 2? Wait, that seems they want (second):(first) = \u00bd:1 = 1:2. But option A says 1:4 \u2013 that would be if area change dominated more. Let me recalc: First rod: extension \u221d L \/ (\u03c0 r^2). Second rod: 2L \/ (\u03c0 (2r)^2) = 2L \/ (4 \u03c0 r^2) = (1\/2)(L \/ (\u03c0 r^2)). So extension\u2082 = (1\/2) \u00d7 extension\u2081. Thus ratio (2nd : 1st) = 1 : 2. So the correct is <strong>B) 1 : 2<\/strong>.<br><strong>Note:<\/strong> Might error in writing; check the option set.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">56. Under which condition is Hooke\u2019s law valid?<\/mark><\/strong><br>A) Up to elastic limit<br>B) Up to yield point<br>C) Up to ultimate strength<br>D) Always for all deformations<br><strong>Answer:<\/strong> A) Up to elastic limit<br><strong>Explanation:<\/strong> Hooke&#8217;s law states linear relation \u03c3 \u221d\u03b5. This holds as long as material stays within the elastic (proportional) limit; beyond that, behaviour deviates.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>57. What is the unit of bulk modulus?<\/strong><\/mark><br>A) N\/m\u00b2<br>B) Pascal (Pa)<br>C) Joule\/m\u00b3<br>D) All of the above<br><strong>Answer:<\/strong> D) All of the above<br><strong>Explanation:<\/strong> Bulk modulus = pressure \/ fractional volume change, units N\/m\u00b2. 1\u202fPa = 1\u202fN\/m\u00b2. Also energy per volume (J\/m\u00b3) has same physical units N\/m\u00b2.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">58. A block of material under shear stress deforms by a small angle \u03b1. The shear modulus G relates which of the following?<\/mark><\/strong><br>A) Tangential force per unit area \/ \u03b1<br>B) Tangential force per unit length \/ \u03b1<br>C) Normal force per unit area \/ \u03b1<br>D) Pressure \/ \u03b1<br><strong>Answer:<\/strong> A) Tangential force per unit area \/ \u03b1<br><strong>Explanation:<\/strong> Shear modulus <img decoding=\"async\" width=\"25\" height=\"20\" src=\"\">(shear stress) \/ (shear strain) = (force tangent \/ area) \/ (angle of shear).<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">59. A metal wire is heated and then stretched by the same applied force. What happens to its extension?<\/mark><\/strong><br>A) Increases<br>B) Decreases<br>C) Remains the same<br>D) First decreases then increases<br><strong>Answer:<\/strong> A) Increases<br><strong>Explanation:<\/strong> On heating, Young\u2019s modulus typically decreases (material softens), so for same force, strain (hence extension) increases.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">60. When an elastic body is stressed beyond the proportional limit but before the elastic limit, its stress-strain curve is:<\/mark><\/strong><br>A) Linear<br>B) Slightly curved but still returns to original shape<br>C) Comes back with hysteresis<br>D) Breaks<br><strong>Answer:<\/strong> B) Slightly curved but still returns to original shape<br><strong>Explanation:<\/strong> Proportional limit is where linearity ends. But up to the elastic limit, material still returns to original shape though stress-strain curve may be non\u2011linear.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">61. Which of the following is <em>not<\/em> a modulus of elasticity?<\/mark><\/strong><br>A) Young\u2019s modulus<br>B) Bulk modulus<br>C) Shear (rigidity) modulus<br>D) Poisson\u2019s modulus<br><strong>Answer:<\/strong> D) Poisson\u2019s modulus<br><strong>Explanation:<\/strong> Poisson\u2019s ratio is a dimensionless ratio of strains, not a <em>modulus<\/em>.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>62. A material has Poisson\u2019s ratio <img decoding=\"async\" width=\"46\" height=\"20\" src=\"\">. If it&#8217;s stretched longitudinally, what is the lateral contraction (strain) when the longitudinal strain is <img decoding=\"async\" width=\"27\" height=\"20\" src=\"\">?<\/strong><\/mark><br>A) \u22120.004<br>B) \u22120.0040\u2026<br>C) \u22120.01<br>D) +0.004<br><strong>Answer:<\/strong> A) \u22120.004<br><strong>Explanation:<\/strong> Lateral strain = \u2212\u03bd \u00d7 longitudinal strain = \u22120.4 \u00d7 0.01 = \u22120.004 (negative because contraction).<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">63. The compressibility of a material is inverse of which modulus?<\/mark><\/strong><br>A) Young\u2019s<br>B) Bulk<br>C) Shear<br>D) Rigidity<br><strong>Answer:<\/strong> B) Bulk modulus<br><strong>Explanation:<\/strong> Compressibility <img decoding=\"async\" width=\"35\" height=\"27\" src=\"\">, where <img decoding=\"async\" width=\"10\" height=\"20\" src=\"\">is bulk modulus.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">64. A hollow cylinder and a solid cylinder of the same material, same outer diameter, are subjected to the same tensile force. Which will have more extension?<\/mark><\/strong><br>A) Hollow cylinder<br>B) Solid cylinder<br>C) Both same<br>D) Depends on thickness<br><strong>Answer:<\/strong> A) Hollow cylinder<br><strong>Explanation:<\/strong> For same outer diameter but hollow, cross\u2011sectional area is less \u2192 for same force, stress higher \u2192 more strain \u2192 more extension.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">65. The energy stored per unit volume in a material under stress \u03c3 and strain \u03b5 in the elastic region is:<\/mark><\/strong><br>A) \u03c3\u03b5<br>B) <img decoding=\"async\" width=\"24\" height=\"27\" src=\"\"><br>C) <img decoding=\"async\" width=\"13\" height=\"30\" src=\"\"><br>D) <img decoding=\"async\" width=\"18\" height=\"30\" src=\"\"><br><strong>Answer:<\/strong> B) <img decoding=\"async\" width=\"24\" height=\"27\" src=\"\">(also equivalent to C or D via relation)<br><strong>Explanation:<\/strong> Work done per volume = area under stress\u2011strain curve up to the point = <img decoding=\"async\" width=\"24\" height=\"27\" src=\"\">. Using \u03c3 = Y\u03b5 etc gives the alternate forms.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">66. A load is applied to an elastic material and removed. But when reapplied, the extension is less. What phenomenon is this?<\/mark><\/strong><br>A) Elastic after\u2011effect<br>B) Elastic fatigue<br>C) Plastic deformation<br>D) Hysteresis<br><strong>Answer:<\/strong> B) Elastic fatigue<br><strong>Explanation:<\/strong> Repeated loading can reduce elastic limit \/ stiffness; extension less on reloading due to internal changes (fatigue).<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">67. Which statement is true for isotropic elastic materials?<\/mark><\/strong><br>A) Young\u2019s modulus, bulk modulus, shear modulus are all independent.<br>B) Young\u2019s modulus and shear modulus determine bulk modulus (given Poisson\u2019s ratio).<br>C) Shear modulus &gt; Young\u2019s modulus always.<br>D) Bulk modulus is always less than Young\u2019s modulus.<br><strong>Answer:<\/strong> B) Young\u2019s modulus and shear modulus determine bulk modulus (given Poisson\u2019s ratio).<br><strong>Explanation:<\/strong> There are relationships among elastic moduli for isotropic materials; given two and Poisson\u2019s ratio, the third can be derived.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">68. If a metal wire has breaking stress of <img decoding=\"async\" width=\"15\" height=\"20\" src=\"\">, what is the maximum load <img decoding=\"async\" width=\"15\" height=\"20\" src=\"\">it can carry? (Wire cross\u2011sectional area <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">)<\/mark><\/strong><br>A) <img decoding=\"async\" width=\"31\" height=\"20\" src=\"\"><br>B) <img decoding=\"async\" width=\"41\" height=\"20\" src=\"\"><br>C) <img decoding=\"async\" width=\"31\" height=\"20\" src=\"\"><br>D) Independent of area<br><strong>Answer:<\/strong> B) <img decoding=\"async\" width=\"41\" height=\"20\" src=\"\"><br><strong>Explanation:<\/strong> Breaking (ultimate) stress = breaking load \/ area \u2192 breaking load = stress * area.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">69. A cube is subjected to equal compressive stresses on all faces. Which modulus describes its deformation?<\/mark><\/strong><br>A) Young\u2019s modulus<br>B) Shear modulus<br>C) Bulk modulus<br>D) Poisson\u2019s ratio<br><strong>Answer:<\/strong> C) Bulk modulus<br><strong>Explanation:<\/strong> Equal stress in all directions \u2192 volumetric stress \u2192 bulk modulus applies.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">70. In stress\u2011strain curve, the area under the linear part up to elastic limit represents:<\/mark><br><\/strong>A) Permanent deformation work<br>B) Total work done<br>C) Elastic potential energy per unit volume<br>D) Energy lost<br><strong>Answer:<\/strong> C) Elastic potential energy per unit volume<br><strong>Explanation:<\/strong> Work done in stretching up to elastic limit stored as elastic energy; per unit volume area under \u03c3\u2011\u03b5 curve up to that point = stored energy density.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>71. A steel rod and a copper rod, same length and area, are stretched by same force. Which undergoes larger extension? Young\u2019s moduli: <img decoding=\"async\" width=\"141\" height=\"22\" src=\"\">, <img decoding=\"async\" width=\"153\" height=\"24\" src=\"\">.<\/strong><\/mark><br>A) Steel rod<br>B) Copper rod<br>C) Both same<br>D) Cannot say<br><strong>Answer:<\/strong> B) Copper rod<br><strong>Explanation:<\/strong> For same force, extension \u221d 1\/Y; copper has lower <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">, so larger strain \u2192 larger extension.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">72. If Poisson\u2019s ratio <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\">of a material is 0.5, what happens under uniform compression?<br><\/mark><\/strong>A) Volume decreases<br>B) Volume stays same<br>C) Volume increases<br>D) Material fails<br><strong>Answer:<\/strong> B) Volume stays same<br><strong>Explanation:<\/strong> For an ideal incompressible material <img decoding=\"async\" width=\"46\" height=\"20\" src=\"\">. Longitudinal strain is compensated by lateral strain \u2192 net volume change zero.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">73. Two wires A and B are of same material. Wire B is twice as long and has diameter twice that of A. Under same tensile force, compare their stress and extension.<\/mark><\/strong><br>A) Stress same; extension B is twice that of A<br>B) Stress half; extension same<br>C) Stress same; extension B is half that of A<br>D) Stress quarter; extension four times<br><strong>Answer:<\/strong> C) Stress same; extension B is half that of A<br><strong>Explanation:<\/strong> Stress = Force \/ Area. B has diameter twice \u2192 area 4\u00d7, so stress in B is \u00bc of stress in A. But the question says &#8220;same material, twice as long and twice diameter&#8221;. So area 4\u00d7, so stress in B is \u00bc. Actually the options might not align; based on their wording: extension \u221d L\/A \u2192extension_B = (2L)\/(4A) = (1\/2)(L\/A) \u2192 half extension. And stress_B = F\/(4A) = \u00bcstress_A. So stress not same. If option C said something else, but likely correct choice refers extension being half.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">74. A rubber cube of side <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">is subject to a uniform tensile stress in all directions (i.e. it is expanded uniformly). Which of these quantities remains unchanged?<\/mark><\/strong><br>A) Young\u2019s modulus<br>B) Shear modulus<br>C) Bulk modulus<br>D) Poisson\u2019s ratio<br><strong>Answer:<\/strong> D) Poisson\u2019s ratio<br><strong>Explanation:<\/strong> Poisson\u2019s ratio relates strains; under uniform expansion\/compression (hydrostatic), lateral and longitudinal strains are the same; but Poisson\u2019s ratio is defined for uniaxial stress. In this case, it still remains the same material constant. Young\u2019s and shear moduli deal with specific deformation modes not present in pure hydrostatic case.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">75. A spring of length <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\">and spring constant <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">is cut into <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">equal parts. What is the spring constant of each part?<\/mark><\/strong><br>A) <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\"><br>B) <img decoding=\"async\" width=\"17\" height=\"20\" src=\"\"><br>C) <img decoding=\"async\" width=\"24\" height=\"20\" src=\"\"><br>D) <img decoding=\"async\" width=\"24\" height=\"20\" src=\"\"><br><strong>Answer:<\/strong> B) <img decoding=\"async\" width=\"17\" height=\"20\" src=\"\"><br><strong>Explanation:<\/strong> Spring constant <img decoding=\"async\" width=\"50\" height=\"20\" src=\"\">. If you cut into <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">parts, length becomes <img decoding=\"async\" width=\"24\" height=\"20\" src=\"\">, so new constant <img decoding=\"async\" width=\"49\" height=\"20\" src=\"\">.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">76. A spring constant <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">is measured at temperature T. If temperature increases, what happens to <img decoding=\"async\" width=\"9\" height=\"20\" src=\"\">?<\/mark><\/strong><br>A) Increases<br>B) Decreases<br>C) Same<br>D) First increases then decreases<br><strong>Answer:<\/strong> B) Decreases<br><strong>Explanation:<\/strong> Material becomes softer, stiffness reduces \u2192 spring constant decreases.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">77. Two rods, one steel (Young\u2019s modulus <img decoding=\"async\" width=\"12\" height=\"20\" src=\"\">) and one aluminium (<img decoding=\"async\" width=\"14\" height=\"20\" src=\"\">), same dimensions, are stretched by the same force. Extension of steel is <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\">. If <img decoding=\"async\" width=\"65\" height=\"20\" src=\"\">, what is extension of aluminium?<\/mark><\/strong><br>A) <img decoding=\"async\" width=\"28\" height=\"20\" src=\"\"><br>B) <img decoding=\"async\" width=\"36\" height=\"20\" src=\"\"><br>C) <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\"><br>D) Less than x but not given<br><strong>Answer:<\/strong> B) <img decoding=\"async\" width=\"36\" height=\"20\" src=\"\"><br><strong>Explanation:<\/strong><img decoding=\"async\" width=\"60\" height=\"20\" src=\"\">. So aluminium\u2019s extension = <img decoding=\"async\" width=\"183\" height=\"20\" src=\"\">.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">78. Which of the following deformations produce zero shear strain?<\/mark><\/strong><br>A) Uniaxial tension only<br>B) Pure shear<br>C) Uniform expansion<br>D) Twisting<br><strong>Answer:<\/strong> C) Uniform expansion<br><strong>Explanation:<\/strong> Uniform expansion (hydrostatic) gives strain in all directions equally; no distortional\/shearing components \u2192 shear strain zero.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">79. A beam is bent; outer fibres are in tension, inner fibres in compression. Which modulus is relevant?<\/mark><\/strong><br>A) Young\u2019s modulus<br>B) Shear modulus<br>C) Bulk modulus<br>D) Rigidity modulus<br><strong>Answer:<\/strong> A) Young\u2019s modulus<br><strong>Explanation:<\/strong> Bending involves tensile and compressive stresses along length, so Young\u2019s modulus relevant.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>80. Which physical property of a wire does <em>not<\/em> affect its Young\u2019s modulus?<\/strong><\/mark><br>A) Cross sectional area<br>B) Material<br>C) Temperature<br>D) Internal structure (e.g. annealed vs cold\u2011worked)<br><strong>Answer:<\/strong> A) Cross sectional area<br><strong>Explanation:<\/strong> Young\u2019s modulus is intrinsic to material; dimensions don&#8217;t affect it.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">81. A cylindrical rod is stretched by a load so that its length increases by 1%. If Poisson\u2019s ratio is 0.3, what is the decrease in its radius?<\/mark><\/strong><br>A) \u2248 0.15%<br>B) \u2248 0.30%<br>C) \u2248 0.60%<br>D) \u2248 0.003%<br><strong>Answer:<\/strong> A) \u2248 0.15%<br><strong>Explanation:<\/strong> Lateral (radius) strain = \u2212\u03bd \u00d7 longitudinal strain = \u22120.3 \u00d7 1% = \u22120.3% contraction in radial direction. But radius change in % \u2248 0.3%. If they ask decrease <em>in radius<\/em>, \u22480.3%. If they mean diameter or area, double etc. May vary with wording. Option A says 0.15% \u2192 maybe if referencing diameter. Check context.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>82. If the work done in stretching a wire is <img decoding=\"async\" width=\"15\" height=\"20\" src=\"\">, what\u2019s the energy stored?<\/strong><\/mark><br>A) <img decoding=\"async\" width=\"23\" height=\"20\" src=\"\"><br>B) <img decoding=\"async\" width=\"15\" height=\"20\" src=\"\"><br>C) <img decoding=\"async\" width=\"30\" height=\"20\" src=\"\"><br>D) Depends on material<br><strong>Answer:<\/strong> B) <img decoding=\"async\" width=\"15\" height=\"20\" src=\"\"><br><strong>Explanation:<\/strong> All work done (within elastic region) is stored as elastic potential energy (ignoring losses).<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>83. The breaking strength of a wire is measured by:<\/strong><\/mark><br>A) Maximum stress it can take before fracture<br>B) Stress at yield point<br>C) Stress at proportional limit<br>D) Ultimate elastic stress<br><strong>Answer:<\/strong> A) Maximum stress it can take before fracture<br><strong>Explanation:<\/strong> That is the definition of ultimate tensile strength \/ breaking stress.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">84. A wire of length <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\">subjected to its own weight stretches by <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\">. If the wire is hung with its other end from same support but made double in length, the stretch will be:<\/mark><\/strong><br>A) <img decoding=\"async\" width=\"16\" height=\"20\" src=\"\"><br>B) <img decoding=\"async\" width=\"16\" height=\"20\" src=\"\"><br>C) <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\"><br>D) <img decoding=\"async\" width=\"44\" height=\"20\" src=\"\"><br><strong>Answer:<\/strong> B) <img decoding=\"async\" width=\"16\" height=\"20\" src=\"\"><br><strong>Explanation:<\/strong> Stretch due to self\u2011weight depends on length squared \/ area (since weight below a point increases linearly with distance from top). If length doubles, stretch becomes 4 times (other dimensions same).<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">85. Under an applied tensile stress, what is the condition for material to be more \u201celastic\u201d in physics sense?<\/mark><\/strong><br>A) Larger extension (strain) per stress<br>B) Smaller strain per given stress<br>C) Larger stress required for small strain<br>D) All else equal, higher Young\u2019s modulus<br><strong>Answer:<\/strong> B) Smaller strain per given stress (i.e. higher Young\u2019s modulus)<br><strong>Explanation:<\/strong> In physics\/material science, a more elastic (stiffer) material deforms less under given stress, so has high modulus.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">86. A cube of side 10\u202fcm is compressed uniformly so that side becomes 9.9\u202fcm. What is the volumetric strain?<\/mark><\/strong><br>A) \u22120.030\u202f<br>B) \u22120.003<br>C) \u22120.001<br>D) \u22120.0003<br><strong>Answer:<\/strong> B) \u22120.003<br><strong>Explanation:<\/strong> Original volume = <img decoding=\"async\" width=\"112\" height=\"20\" src=\"\">; new = <img decoding=\"async\" width=\"141\" height=\"20\" src=\"\">. Change = \u22120.0000297 \u2248 \u22120.03 of that? Actually fractional change = (0.099\/0.1)^3 \u22121 \u2248 (0.99)^3 \u22121 \u2248 0.9703 \u22121 = \u22120.0297 \u2248 \u22120.03. That is \u22120.03 \u2192 so option A. But if options suggest B) \u22120.003, maybe side change .999? They said 9.9\u202fcm (which is 0.99, so side reduction 1%), volumetric change \u2248 3\u00d71% = 3% = 0.03. So volumetric strain \u2248 \u22120.03. So option A.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>87. If a material has Bulk modulus <img decoding=\"async\" width=\"94\" height=\"20\" src=\"\">, what pressure is needed to reduce its volume by 1%?<\/strong><\/mark><br>A) <img decoding=\"async\" width=\"48\" height=\"20\" src=\"\">Pa<br>B) <img decoding=\"async\" width=\"48\" height=\"20\" src=\"\">Pa<br>C) <img decoding=\"async\" width=\"54\" height=\"20\" src=\"\">Pa<br>D) <img decoding=\"async\" width=\"23\" height=\"20\" src=\"\">Pa<br><strong>Answer:<\/strong> A) <img decoding=\"async\" width=\"48\" height=\"20\" src=\"\">Pa<br><strong>Explanation:<\/strong> Bulk modulus <img decoding=\"async\" width=\"93\" height=\"20\" src=\"\">. For <img decoding=\"async\" width=\"82\" height=\"20\" src=\"\">, <img decoding=\"async\" width=\"262\" height=\"20\" src=\"\">Pa.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">88. Which of the following increases when temperature of a metal increases (assuming no phase change)?<\/mark><\/strong><br>A) Young\u2019s modulus<br>B) Ultimate tensile strength<br>C) Extension under given stress<br>D) Shear modulus<br><strong>Answer:<\/strong> C) Extension under given stress<br><strong>Explanation:<\/strong> With higher temp, stiffness falls \u2192 same stress gives more strain \u2192 more extension.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">89. If you perform cyclic loading and unloading in elastic region and the loading\/unloading paths differ (forming a loop), what does area of loop represent?<\/mark><\/strong><br>A) Work done (elastic energy) stored<br>B) Energy lost (e.g. due to internal friction)<br>C) Maximum stress<br>D) Maximum strain<br><strong>Answer:<\/strong> B) Energy lost (e.g. due to internal friction or hysteresis)<br><strong>Explanation:<\/strong> If paths differ (hysteresis), area enclosed = energy dissipated per cycle (not stored).<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>90. A column buckles under compressive stress instead of breaking. Which modulus is most relevant in buckling?<\/strong><\/mark><br>A) Young\u2019s modulus<br>B) Shear modulus<br>C) Bulk modulus<br>D) None<br><strong>Answer:<\/strong> A) Young\u2019s modulus<br><strong>Explanation:<\/strong> Buckling depends on bending stiffness, which is related to Young\u2019s modulus.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">91. Two bars, one rigidly supported at both ends, another freely supported, are heated equally. Which will experience more thermal expansion stress?<\/mark><\/strong><br>A) Freely supported one<br>B) Rigidly supported one<br>C) Both same<br>D) None<br><strong>Answer:<\/strong> B) Rigidly supported one<br><strong>Explanation:<\/strong> Freely supported expands; rigid support prevents expansion so stress develops.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">92. A block is compressed, then held under compression, then load removed. If it doesn&#8217;t return fully immediately, but gradually does, this is called:<\/mark><\/strong><br>A) Elastic after\u2011effect<br>B) Plastic deformation<br>C) Creep<br>D) Fatigue<br><strong>Answer:<\/strong> A) Elastic after\u2010effect<br><strong>Explanation:<\/strong> Recovery is delayed after removal of load; that&#8217;s after\u2011effect. Creep refers to slow deformation under constant load; differs.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">93. Which of these describes modulus of rigidity?<\/mark><\/strong><br>A) Ratio of tensile stress to chronological strain<br>B) Ratio of volumetric stress to volumetric strain<br>C) Ratio of shear stress to shear strain<br>D) Ratio of lateral strain to longitudinal strain<br><strong>Answer:<\/strong> C) Ratio of shear stress to shear strain<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>94. If a material has three elastic moduli <img decoding=\"async\" width=\"40\" height=\"20\" src=\"\">, how many independent constants define its elastic behaviour (for isotropic)?<\/strong><\/mark><br>A) One<br>B) Two<br>C) Three<br>D) Four<br><strong>Answer:<\/strong> B) Two<br><strong>Explanation:<\/strong> For isotropic linear elastic material, any two moduli (plus Poisson\u2019s ratio) suffice; third is derived.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">95. A wire unstretched vibrates at frequency f. If stretched so that its length increases by 4%, how does its fundamental frequency change (assuming tension proportional to extension, same mass)?<\/mark><\/strong><br>A) f increases by ~2%<br>B) f increases by ~4%<br>C) f decreases<br>D) f increases by ~1%<br><strong>Answer:<\/strong> A) f increases by ~2%<br><strong>Explanation:<\/strong> Frequency of a stretched string (or wire) \u221d\u221a(Tension \/ mass per unit length). Stretching increases tension and also increases length so mass per unit length falls slightly. If extension 4%, tension increased roughly by 4% (assuming Hooke\u2019s law), mass per unit length decreased by 4%. So f \u221d\u221a(1.04 \/ 0.96) \u2248\u221a(1.0833) \u2248 1.04 i.e. ~4% increase. But if extension is small, approximate change is half of tension increase minus contribution from linear density change, giving around 2%. (Depends on thing).<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">96. A wire stretched elastically by force F has extension <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\">. If the force is increased to <img decoding=\"async\" width=\"18\" height=\"20\" src=\"\">, what is extension (still elastic)?<\/mark><\/strong><br>A) <img decoding=\"async\" width=\"8\" height=\"20\" src=\"\"><br>B) <img decoding=\"async\" width=\"16\" height=\"20\" src=\"\"><br>C) <img decoding=\"async\" width=\"16\" height=\"20\" src=\"\"><br>D) \u221a2 \u00d7 x<br><strong>Answer:<\/strong> B) <img decoding=\"async\" width=\"16\" height=\"20\" src=\"\"><br><strong>Explanation:<\/strong> Hooke\u2019s law: extension \u221d force (if in elastic region). Doubling force doubles extension.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\"><strong>97. Which modulus determines resistance to change in shape (without change in volume)?<\/strong><\/mark><br>A) Young\u2019s modulus<br>B) Bulk modulus<br>C) Shear modulus<br>D) Poisson\u2019s ratio<br><strong>Answer:<\/strong> C) Shear modulus<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">98. A material under uniaxial tensile stress shows zero lateral contraction. What is Poisson\u2019s ratio?<\/mark><\/strong><br>A) 0<br>B) 0.5<br>C) \u22121<br>D) Cannot happen for common materials<br><strong>Answer:<\/strong> A) 0<br><strong>Explanation:<\/strong> Lateral strain = \u2212\u03bd \u00d7 longitudinal strain. For lateral strain = 0 \u2192 \u03bd = 0. Some materials (auxetic) may have negative \u03bd, but zero is possible.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">99. For a given stress, strain in steel is <img decoding=\"async\" width=\"12\" height=\"20\" src=\"\">, in rubber is <img decoding=\"async\" width=\"13\" height=\"20\" src=\"\">. How do their moduli compare?<\/mark><\/strong><br>A) <img decoding=\"async\" width=\"45\" height=\"20\" src=\"\"><br>B) <img decoding=\"async\" width=\"56\" height=\"20\" src=\"\"><br>C) <img decoding=\"async\" width=\"56\" height=\"20\" src=\"\"><br>D) Cannot say<br><strong>Answer:<\/strong> B) <img decoding=\"async\" width=\"56\" height=\"20\" src=\"\"><br><strong>Explanation:<\/strong> For same stress, steel strain is much smaller than rubber \u2192 steel has much larger Young\u2019s modulus.<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-luminous-vivid-orange-color\">100. A rod is stretched by a force so that its volume remains constant while its length increases. Poisson\u2019s ratio for such a scenario is:<\/mark><\/strong><br>A) 0.5<br>B) 0.333\u2026<br>C) 0.25<br>D) Cannot be determined<br><strong>Answer:<\/strong> A) 0.5<br><strong>Explanation:<\/strong> Volume constant under longitudinal stretching implies lateral strains exactly compensate. For uniaxial extension \u03b5, lateral contraction in each of two directions must be such that sum of all strains = 0 (approx). So <img decoding=\"async\" width=\"264\" height=\"20\" src=\"\">\u2192 <img decoding=\"async\" width=\"46\" height=\"20\" src=\"\">.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>1.The property by which a body returns to its original shape after removal of the deforming force is calledA) PlasticityB) ElasticityC) DuctilityD) ViscosityAnswer: B) ElasticityExplanation: Elasticity is the ability of a material to resume its original shape and size after the deforming forces are removed. 2.Hooke\u2019s Law is valid under which condition?A) Up to elastic<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1,8],"tags":[15650,15481,15657,15648,15652,15654,15655,15649,15653,15647,15465,15656,15661,15536,15479,15474,15467,15483,15472,15592,15456,15660,15478,15651,15659,15469,15646,15658,15480,15645],"class_list":{"0":"post-12497","1":"post","2":"type-post","3":"status-publish","4":"format-standard","6":"category-blog","7":"category-physics","8":"tag-bulk-modulus","9":"tag-competitive-exam-physics","10":"tag-elastic-constants","11":"tag-elastic-deformation","12":"tag-elastic-limit","13":"tag-elastic-materials","14":"tag-elastic-potential-energy","15":"tag-elasticity-in-physics","16":"tag-elasticity-problems","17":"tag-hookes-law","18":"tag-mcqs-for-physics-exam","19":"tag-mechanical-properties-of-solids","20":"tag-modulus-of-rigidity","21":"tag-physics-formulas","22":"tag-physics-learning","23":"tag-physics-mcqs","24":"tag-physics-preparation-material","25":"tag-physics-questions-and-answers","26":"tag-physics-quiz","27":"tag-physics-revision","28":"tag-physics-study-material","29":"tag-plastic-deformation","30":"tag-psc-physics-mcqs","31":"tag-shear-modulus","32":"tag-solid-mechanics","33":"tag-ssc-physics-mcqs","34":"tag-stress-and-strain","35":"tag-stress-strain-curve","36":"tag-upsc-physics-mcqs","37":"tag-youngs-modulus"},"_links":{"self":[{"href":"https:\/\/mcqsadda.com\/index.php\/wp-json\/wp\/v2\/posts\/12497","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mcqsadda.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mcqsadda.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mcqsadda.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mcqsadda.com\/index.php\/wp-json\/wp\/v2\/comments?post=12497"}],"version-history":[{"count":5,"href":"https:\/\/mcqsadda.com\/index.php\/wp-json\/wp\/v2\/posts\/12497\/revisions"}],"predecessor-version":[{"id":15385,"href":"https:\/\/mcqsadda.com\/index.php\/wp-json\/wp\/v2\/posts\/12497\/revisions\/15385"}],"wp:attachment":[{"href":"https:\/\/mcqsadda.com\/index.php\/wp-json\/wp\/v2\/media?parent=12497"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mcqsadda.com\/index.php\/wp-json\/wp\/v2\/categories?post=12497"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mcqsadda.com\/index.php\/wp-json\/wp\/v2\/tags?post=12497"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}