Strain is defined as ratio of
The strain is defined as the ratio of change in dimension to the original dimension.
If ‘δl’ changes in the length and ‘l’ is the original length, strain = δl/l
Consider the following stress-strain diagram and match the following:
List - I
List - II
1. Hard rubber
2. Soft rubber
3. Structural steel
4. Aluminium alloy
Young's modulus is defined as the ratio of
The linear relationship between stress and strain for a bar in simple tension or compression can be expressed by the equation
in which Eis a constant of proportionality known as modulus of elasticity for the material. The modulus of elasticity is the slope of the stress- strain diagram in the linearly elastic region and its value depends upon the particular material being used.
Match List-I (Material) with List-ll (Young’s modulus):
The permanent mode of deformation of a material known as ____________
Plasticity is defined as the property of a material due to which it is permanently deformed due to loading. Elasticity is the temporary form of deformation. Twinning and Slip are mechanisms of Plastic deformation.
A thin mid steel wire is loaded by adding loads in equal increments till it breaks. The extensions noted with increasing loads will behave as under
At first, the strain is proportional to strain or elongation is proportional to the load giving a straight-line relationship.
A further increase in the load after yield load will cause marked deformation in the whole volume of the metal. The maximum load which the specimen can withstand without failure is called the load at the ultimate strength.
Match List-1 (Materia!) with List-ll (Poisson’s Ratio)
During a tensile test on a specimen of 1 cm2 cross-section, maximum load observed was 80 kN and area of cross-section at neck was 0.5 cm2. UTS of specimen is
= 800 MPa
A prismatic bar of circular cross-section is loaded by tensile forces P= 90 kN. The bar has length L = 3 m and diameter d = 30 mm. If is made of aluminium with modulus of elasticity E = 70 GPa and Poisson’s ratio v = 1/3. What is the increase in volume ΔV of the bar?
Resilience of a material is considered when it is subjected to
Resilience represent the ability of the material to absorb energy within the elastic range.