What is poisson ratio?(पाइजन अनुपात क्या है?)
Poisson's ratio measures the ratio of the cross-sectional area in the linear direction. In this way, we can say that the lateral deformation is the direction along the diameter and the area along the line is the longitudinal direction. Poisson's ratio describes the lateral and linear deformations in the shape of the ratio. This is called Poisson's ratio. Poisson's ratio is a negative characteristic of linear and linear fibers in some areas, because the material has expansion and contraction characteristics. However, when it decreases, it shows a negative value. This number is very important for determining the components of the deformation due to the applied load. We can design the structure according to its yield strength and put a lot of weight on itWhat is poisson ratio?(पाइजन अनुपात क्या है?) In hindi
What is Poisson's Ratio?
पाइजन अनुपात क्या है?
The negative relationship between transverse strain and lateral or axial strain is known as Poisson's ratio. It is identified with the Greek letter \"nu\" and takes its name from Siméon Poisson. Poisson's ratio is represented as mew (μ) or 1/m. In the same context, different materials have different Poisson's ratios. The maximum value of Poisson's ratio is 0.5 and the minimum value is 0. Exceptionally, human tissue is (-1) Poisson's ratio. There is no unit of Poisson's ratio.
We can say that Poisson's RatioWhat is poisson ratio?(पाइजन अनुपात क्या है?) In hindi
Poisson's ratio is defined as the ratio of lateral contraction (expansion) strain to longitudinal extension (contraction) strain when an object is subjected to an external tensile (compression) force along its longitudinal axis. When a solid bar is subjected to a tensile force along its longitudinal axis, the length of the bar increases in the direction of force application. Because the molecules in solids are close together, the density of solids remains nearly constant. Therefore, to keep its volume unchanged, the solid contracts in its lateral direction. The ratio of the size changes to their original size in the longitudinal and lateral directions are called "longitudinal strain" and "lateral strain", respectively. Poisson's ratio is expressed as the ratio of this lateral strain to the longitudinal strain, with a negative sign in front. The Poisson ratio is named after the French mathematician Simeon Denis Poisson. Poisson's ratio plays a vital role in engineering design. It is used to calculate the stress and deflection of beams, shafts, rotors, etc. when subjected to external loads and thus helps optimize engineering designs.What is poisson ratio?(पाइजन अनुपात क्या है?) In hindi
Hence the expression for Poisson's Ratio will be:
ν = −Transverse Strain/Longitudinal Strain
ν = −ϵy/ϵx
Substitute ϵy and ϵx by ϵt and ϵl respectively to get the following expression of Poisson's Ratio:
ν = −ϵt/ϵl
Since the object contracts in the transverse direction when subjected to an axial tensile load, the change in size in this direction is negative and hence the transverse strain. Conversely, the object expands in the longitudinal direction, so its size change is positive and the corresponding longitudinal strain is positive. So, to express Poisson's ratio as a positive number, a negative sign is inserted into its mathematical expression.
Poisson's Ratios of some Materials -
Some materials the Poisson's ratio is in the range 0 - 0.5. Typical Poisson's Ratios for some common materials are indicated below.
Material Poisson's Ratio is denoted by - μ -
Upper limit 0.5
Aluminum 0.334
Aluminum, 6061-T6 0.35
Aluminum, 2024-T4 0.32
Beryllium Copper 0.285
Brass, 70-30 0.331
Brass, cast 0.357
Bronze 0.34
Clay 0.41
Concrete 0.1 - 0.2
Copper 0.355
Cork 0
Glass, Soda 0.22
Glass, Float 0.2 - 0.27
Granite 0.2 - 0.3
Ice 0.33
Inconel 0.27 - 0.38
Iron, Cast - gray 0.211
Iron, Cast 0.22 - 0.30
Iron, Ductile 0.26 - 0.31
Iron, Malleable 0.271
Lead 0.431
Limestone 0.2 - 0.3
Magnesium 0.35
Magnesium Alloy 0.281
Marble 0.2 - 0.3
Molybdenum 0.307
Monel metal 0.315
Nickel Silver 0.322
Nickel Steel 0.291
Polystyrene 0.34
Phosphor Bronze 0.359
Rubber 0.48 - ~0.5
Sand 0.29
Sandy loam 0.31
Sandy clay 0.37
Stainless Steel 18-8 0.305
Steel, cast 0.265
Steel, Cold-rolled 0.287
Steel, high carbon 0.295
Steel, mild 0.303
Titanium (99.0 Ti) 0.32
Wrought iron 0.278
Z-nickel 0.36
Zinc 0.331
What is poisson ratio?(पाइजन अनुपात क्या है?) In hindi
यदि आपने अभी तक हमारे Whatsapp group click me ... को ज्वाइन नहीं किया है तो जल्द ही ज्वाइन करें ऊपर लिंक पर क्लिक करें।
टिप्पणियाँ
एक टिप्पणी भेजें
Leave a Comment