Final answer:
The modulus of elasticity is found by performing a tensile test, determining stress and strain, and dividing the stress by the strain. The original diameter is used to calculate the cross-sectional area, and the gauge length is used to calculate strain during the tension test.
Step-by-step explanation:
The modulus of elasticity, also known as Young's modulus, is a measure of the stiffness of a material. It is defined as the ratio of the stress applied to a material to the resulting strain within the elastic limits. When you have the original diameter and gauge length of a cylindrical specimen, you can find the modulus of elasticity by conducting a tension test.
Steps to find the modulus of elasticity:
- Determine the cross-sectional area of the specimen using the original diameter.
- Perform a tensile test to apply a force on the specimen and measure the resulting change in length (elongation).
- Calculate stress using the applied force and the cross-sectional area.
- Calculate strain by dividing the elongation by the original gauge length.
- Calculate the modulus of elasticity as the ratio of stress to strain within the elastic range.
For example, if your specimen has an original diameter of 10mm and a gauge length of 50mm, and during the tensile test the specimen elongated 0.5mm under a certain force, you can use these values to calculate the modulus of elasticity through the above steps.