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| Young's Modulus |
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Young's modulus is number representing the ratio of stress to strain for a wire or bar of a given substance. |
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Young's modulus is usually measured in pounds per square inch or dynes per square centimeter. |
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According to Hooke's law the strain is proportional to stress, and therefore the ratio of the two is a constant that is commonly used to indicate the elasticity of the substance.
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It is also known as the Young modulus, modulus of elasticity, elastic modulus or tensile modulus. |
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Young's modulus is named after Thomas Young, the 18th century British scientist.
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Young's modulus is the ratio of stress, which has units of pressure, to strain, which is dimensionless; therefore Young's modulus itself has units of pressure. |
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Young's modulus is represented by the slope E = ΔS / Δε
of the initial straight segment of the stress-strain diagram.
More correctly, E is a measure of stiffness, having the same
units as stress: pounds per square inch or pascals. |
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When stress and strain are not directly proportional, E may be represented as the slope of the tangent or the slope of the secant connecting two points on the stress-strain curve.
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