Strain in general

Strain is a key concept that describes how a material deforms in response to applied stress. This digital learning path explains strain in general.

Motivation phase
Picture

Carefully examine the picture and check if you see anything unusual. There are plastic things, like a plastic bottle, a plastic cap, a plastic straw, and others, that are broken. In mechanics we would say that broken plastic things are plastic deformed. Opposite to plastic deformation, there is elastic deformation, meaning the material's ability to return to its original state, or original dimensions and position, after the influence of an external force. It is thanks to strain that we understand the material's capabilities when subjected to force.
Picture is generated by Ana Marketin-Sedlar with an AI toll Freepic.

Information phase
Presentation

Watch the presentation and learn general information about strain. There is Quizziz game in the end of the presentation. Play the game and check your knowledge.

Information phase
Presentation

This presentation highlights terms and definitions related to the strain and calculation. There is Quizziz game in the end of the presentation. Play the game and check your knowledge.

Information phase
Watch the video

Watch the video about elongation at break which plays the main role in 3D printing and other technologies.

Consolidation phase
Experiment

Find several objects made of different materials that you are allowed to break, such as a wooden stick, a plastic cup, a paper straw, and slowly bend them. Before bending, set a stopwatch to measure the time it takes for each object to break. While bending, observe the deformation of the objects and try to identify the elastic and plastic limits of each material. This experiment is more enjoyable when done in pairs to divide tasks of timing and bending objects. Additionally, discuss the results with your partner and determine if they align with the initial hypothesis.
Picture is generated by Ana Marketin-Sedlar with an AI toll Freepic.

Resource information

Level: Level 3
Subject: Mechanics
Language: English
Estimated time to complete: 15+ minutes