[ExI] A Lawn sprinkler

codehead at readysetsurf.com codehead at readysetsurf.com
Wed Jun 13 16:39:59 UTC 2007

On 13 Jun 2007 at 1:19, John K Clark wrote:

> You pump water through an S shaped lawn sprinkler and it spins
> counterclockwise, but suppose you put the sprinkler in a tank of water and
> pump water out not in. What direction will the sprinkler rotate? As an
> undergraduate Richard Feynman actually tried the experiment but he was not
> successful; the tank burst flooding the lab and he almost got kicked out of
> school. However he later figured out what the answer must be.

This is a canonical problem in many physics curricula.

So perhaps the physicists on the list should recuse themselves?

(grad student in physics)

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