A quiz:
If you are a brand-name (say like "Barbie-less") for a previously large chain store... one where America previously shopped; and you sell dishwashers....
And said dishwasher has a center twirling arm to spray water around... and the arm is secured with a large plastic screw with big shoulder.
Now, you can put the jets on the arm two ways: one rotates the arm so that the screw, if anything, tightens itself...
And the other so the screw LOOSENS itself....so it backs out, falls out, as does the arm....
So which way would you design it to rotate? Why?
Justify your response. 10 points. Responses quoting Feynman get extra credit.
Question 2: Suppose your firm choose badly. How would solve it in the field?
a) Epoxy screw into place
b) Throw arm away, with screw; tell customer it's an upgrade.
c) Figure out how to get screw to stop doing that.