ABC Article Directory banner displaying blue butterfly logo. Click to go directly to the main Homepage


Proportional Limit Related to Hooke's






     What is proportional limit? How is proportional limit related to Hooke's law? Read to find the answers... Material science and mechanics are branches of physics devoted to the study of chemical and physical properties of every single material that finds applications in engineering and pure science. While the reductionist approach of studying the properties of materials at atomic or molecular level may help us understand certain physical properties, it cannot predict how matter will behave in bulk, when the intermolecular forces come into play. In extreme engineering applications, materials need to be tested for their strength to determine their yield point or tensile strength limit. The macroscopic forces come into play here. One of the associated physical properties, which is measured when conducting stress tests, is the proportional limit. The aim of writing this article is to explain what is proportional limit and how does it determine the strength of a material.

Before I can explain what is meant by proportional limit, some of the basic physics ideas associated with this concept, like stress and strain need to be explained. So here is a short introduction to concepts of stress and strain, along with the statement of Hooke's law, which will help you grasp the idea of proportional limit.

About Stress & Strain

The strength of a material is measured by how it responds to stress and strain. Stress is a measure of the internal force per unit area acting on a body when it is subjected to deforming forces. The unit of stress is same as that of pressure and it's equal to Newton per square meter.

In engineering terms, strain is a ratio of change in the dimensions of anybody with respect to its original dimensions. It is distortion of the body that occurs due to the application of external forces on it. It is the shifting of layers of the material, which occurs under application of deforming force.

Hooke's law is a relation between stress and strain felt by a deforming body. This approximate law states that the strain felt by a material is directly proportional to stress, within the elastic limit. The elastic limit is the point beyond which, if an object is stretched, it's permanently deformed. The proportionality factor between stress and strain is known as the modulus of elasticity of the material. With all those basics cleared out, you are now in a position to study the proportional limit.

What is Proportional Limit?

In the simplest of words, proportional limit is the maximum amount of stress that an object can handle while still obeying the Hooke's law. In other words, it is the highest limit of stress that a material may be subjected to, while still maintaining a linear relation with strain.

If you plot a curve of stress against strain, there will be a linear relation between stress and strain, until the yield point is reached. After this point the strain goes on increasing without increase in stress. The highest value of stress, just before the yield point is reached, is known as the proportional limit.

If you apply force beyond this limit, the proportionality relation between stress and strain is no longer maintained. Apply more stress beyond this point, and you may deform the material permanently. There is no proportional limit formula or proportional limit equation per se, as the exact value of maximum stress that a material can take, is entirely dependent on its internal molecular or crystalline structure.

To conclude, proportional limit is the highest level of stress that a material like a metal can be subjected to, without pushing it beyond the point where it stops obeying the proportionality relation between stress and strain. If you pursue production engineering or mechanical engineering, you will know that studying the properties of materials like their proportional limit and grading them according to their yield strength is one of the most important tasks of a designer and production manager. Hope this article has cleared out the concept of proportional limit for you.

For more information: http://www.electrocomputerwarehouse.com






Article Source: http://www.abcarticledirectory.com

Electro Computer Warehouse - North America's Largest Reseller of Cheap Computers, Used Computers Refurbished Computers and Laptops


Posted on 2012-04-11, By: *

* Click on the author's name to view their profile and articles!!!


Note: The content of this article solely conveys the opinion of its author.


Animated RSS Symbol for the ABC Article Directory rss category feed ... Get Every New Science World Article Delivered Instantly!



Facebook Comments


" data-width="470" data-num-posts="10">




Cartoon image of a figure holding a magnifying glass looking for articles in the ABC Article Directory

Still Searching? Last Chance to find what you're looking for with a Google Custom Search!



Custom Search

Or.... You can search this site using our Bing Custom Search!

Bing




Did You Like/Dislike This Article? Give It YOUR Rating!

Please Rate this Article

No Ratings Yet. Be The First To Rate This Article





/EDF Publishing. All rights reserved. Script Services by: Sustainable Website Design
Use of our free service is protected by our Privacy Policy and Terms of Service | Contact Us

User published content is licensed under a Creative Commons Attribution-No Derivative Works 3.0 Unported License
.
Increase your website traffic with Attracta.com

Valid CSS!


ABOUT SSL CERTIFICATES
Date:


Powered by ABC Article Directory