February 24, 2007
Creative exam answers
Now this is funny.
Posted by James Hamilton at February 24, 2007 11:36 AMdigg this | reddit
This is polular in China, too.
Posted by: Gracia at February 24, 2007 11:35 PM
That is pretty funny Dr Hamilton.
The best one I remember was by a friend of mine in chem engineering at U Minnesota circa 1980.
We were asked to design a packed tower gas scrubber... Given flows rates & compositions of inlet & outlet gases calculate height, diameter and number of 'theoretical trays'.
A packed tower is just a big vertical tube filled with thingies like this... see the 'random packing section' that was what we were asked to 'design'.
She inverted the equilibrium relationship & instead of coming up with a tower 30 ft in height she came up with one about 3 ft high.
It was in one of those scrambles of an exam where you were lucky to finish let alone get most of the stuff right (typical means in the 50s with high score at maybe 80 out of 100 possible)...
She looked but did NOT have enough time to go back and find the error & fix. Instead she wrote:
"Obviously I've made an error somewhere. Or MAYBE we've come across a new marketing opportunity... PORTABLE SCRUBBERS!!!"
She then drew a picture of a short squat scrubber with wheels & a handle being pulled by a stick man.
The prof gave her almost all the partial credit, showed her the error & used this as an example to the whole class - that it is possible in the heat of analysis to err... but to have the sense to realize the numbers don't pass the sniff test & point that out is invaluable & the key to being sure that good numbers eventually result.
Too bad that test isn't still floating around out there somewhere.
Posted by: dryfly at February 25, 2007 07:17 PM