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philipc
Mar15-04, 09:54 PM
I've yet to taken a statics class yet, only physics one, but I'm having a hard time trying to define what an extension is on one of my home work problems.
The problem is kind of long(about a page long), hopefully I will be giving a enough info on my problem. Here goes

You have a pin jointed framework and all the members are connected to the wall and connected together at point A. We have two external forces, one going towards pt A and anther pointing downward from pt A. We want to find the movement of point when the forced are applied.

I'm to write a program that solves the problem, but I'm not sure what "extension" is? I've been given a formula for it, e = -d1*cos(@) + d2sin(@)

Philip

gnome
Mar15-04, 10:17 PM
Can't tell what you're referring to without a context.

At least give the full sentence in which "extension" appears.

philipc
Mar15-04, 10:51 PM
I just re-read the problem, and the word "extensions" is not really used in a complete sentence, but I found another formula for it, e1 = k1*T1 where k is called the flexibility of the member and T is the tension on the member. Here is a little more detail about the framework, it helps? With this kind of joint there is no tendency to bend the member, and the only forces that are present are tensile or compressive forces in the members. It is assumed that the weights of the members are negligible and the lengths of the members are such that if the external forces F1 and F2 are zero, there are no stresses in the members.

The only other time the word extension is use is in this sentence.
"In this project you are to develop a Matlab script that will determine the distances, extensions and tensions for such a pin-jointed framework containing x number of pins"

Philip

gnome
Mar15-04, 11:10 PM
I'm not sure, but isn't that just referring to lengthwise stretching of the members?