The discussion revolves around the relationship between strain and change in length as described by Hooke's Law. Participants are exploring the definitions and units associated with strain and change in length, as well as their implications in mechanical contexts.
The discussion is ongoing, with various interpretations being explored. Some participants have provided guidance on looking up definitions and units in textbooks or online resources. There is an acknowledgment of the importance of understanding these concepts for further learning.
Some participants express frustration with the forum's rules against providing direct answers to homework questions, emphasizing a desire for clarity on the topic instead. There is also a mention of the relevance of understanding the unitless nature of strain in educational contexts.
Orodruin said:It should be noted that Hooke's law relates stress ##\sigma## (i.e., the applied force per area) to strain ##\epsilon## as ##\sigma = E\epsilon##, where ##E## depends on the material. Thus, from force and cross-sectional area, you can know the strain, but not the change in length (for that you also need to know the original length).