What is the Elongation Due to Stress and Strain in Steel?

Thread starter archaic
Start date Apr 22, 2020
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Elongation Strain Stress

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The discussion focuses on calculating elongation due to stress and strain in steel, using specific formulas. The stress is calculated to be approximately 2.1 million Pascals, with Young's modulus for steel given as 20 x 10^10 Pascals. The ratio of elongation to original length is found to be about 1.1 x 10^-5. Consequently, the change in length is determined to be approximately 2.3 x 10^-5 meters. The calculations confirm the accuracy of the results, despite initial apprehension about the online homework platform.

Apr 22, 2020

archaic

Homework Statement: A vertical solid steel post of diameter d = 21 cm and length L = 2.20 m is required to support a load of mass m = 7500 kg . You can ignore the weight of the post.
What is the stress in the post?
What is the strain in the post?
What is the change in the post's length when the load is applied?

Relevant Equations: Stress is ##F/A##, and ##Y=\frac{F}{A}\frac{L}{\Delta L}##

$$\text{stress}=\frac{7500\times9.8}{0.105^2\pi}\approx2.1\times10^6\,Pa$$
##Y=20\times10^{10}\,Pa## for steel.
$$\frac{\Delta L}{L}=\frac{\text{stress}}{Y}\approx1.1\times10^{-5}$$
$$\Delta L\approx2.3\times10^{-5}\,m$$

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Apr 22, 2020

archaic

It's correct. Sorry, I get scared of the online homework platform sometimes.

Last edited: Apr 22, 2020

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