Saturday, January 28, 2012

Symmetry: Why Engineering is for Men

There is one particular shirt I have in the closet, and the first time I wore it, I don't know how many guys (brother, friends, boyfriend, father) asked me where the other strap went.  Let's show a demonstration:

I thought that this was maybe a joke put on by the guys around me, until I asked guys, "What do you think when you see this shirt?" Most of them answer the same thing as above.  So point proven.

Maybe this is why guys enjoy engineering...everything is about symmetry.  But in their minds, they think about the following Free Body Diagram:

But how does the shirt stay up? This is why guys are so hesitant about the situation...What holds the shirt up?! But our Free Body Diagram isn't complete...

YAY! We didn't break Statics!
 The pressure from the elastic helps to allow the moments on the shirt. Now the free body diagram is complete.

And that is engineering for you.  Maybe the gals do have it figured out :-P

*Image courtesy of and Serena's wonderful drawing skills via Microsoft Powerpoint.


  1. Well now you have to prove how a STRAPLESS shirt stays up! :D

  2. Good one! Well a strapless shirt stays up using 2 "Elastic Pressure" forces, 1 on either side. That problem is actually a little more simple.:-D

  3. Thank you for the good writeup. It in fact was a amusement account it. Look advanced to far added agreeable from you! By the way, how could we communicate?

    1. Feel free to contact me via email at

  4. Maybe the strap is like a zero force member. The straps on half my shirts fall off my shoulder anyway and luckily I'm not flashing anyone so I'm guessing it's a negligible force if anything.