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Mechanical engineering One liner

  • Hooke's law holds good up to Limit of proportionality.
  • Young's modulus is defined as the ratio of Longitudinal stress and longitudinal strain.
  • The materials having same elastic properties in all directions arc called Isotropic materials.
  • A thin mild steel wire is loaded by adding loads in equal increments till it breaks. The extensions noted with increasing loads will behave as under Increase uniformly first and then increase rapidly.
  • Modulus of rigidity is defined as the ratio of Shear stress and shear strain.
  • The ultimate tensile stress of mild steel compared to ultimate compressive stress is More.
  • The impact strength of a material is an index of its Toughness.
  • The Young's modulus of a wire is defined as the stress which will increase the length of wire compared to its original length with same amount.
  • Percentage reduction of area in performing tensile test on cast iron may be of the order of zero.
  • The intensity of stress which causes unit strain is called Modulus of elasticity.
  • True stress-strain curve for materials is plotted between Load/instantaneous cross-sectional area.


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