Don't understand what the problem wants.

[Physics_wiz]

Ok, this problem is from my Intermediate Mechanics of Materials class. Given are two tables for a specimen of medium-carbon steel with initial diameter 0.503 in and gauge length 2 in. The two tables are labeled "Elastic State" and "Plastic State".

The first table gives the Load vs. Elongation...Load ranging from 1,000 lbf to 9,200 lbf and Elongation ranging from 0.0004 into 0.0089 in.

The second table gives load vs. Area. Load ranging from 8,800 lbf to 14,800 lbf and Area ranging from 0.1984 in^2 to 0.1077 in^2.

The question is to plot the engineering stress-strain diagram using two scales for the unit strain (epsilon), one from zero to about 0.02 in/in and the other from zero to maximum strain.

I don't understand what it means by the bold part. Also, how can I plot stress vs strain for the plastic part if I only have the change in area...I don't have the elongation so I can't find strain.

Any help would be appreciated.

PS. Should I be posting this in the Engineering section instead?

 

[Gelsamel Epsilon]

I think it's asking you to plot a graph where the first part is in a separate scale to the 2nd, so that the graph is easier to look at. The first scale should be used from 0 to 0.02in and the next from there on.

It's so that a squiggly graph that goes all over the place is changed into a curve or a straight line with just multiple scales.

I've only done the first bit of Stress-strain so I don't have any idea how you would actually go about this question.