Friday, July 12, 2013

Ddolan/ Flow of draining water

My Name is Deb Dolan and I’m from Brockton Ma.  I love water; salt water, fresh water and swimming pools.  I’m spend most of my disposable income on the water, near the water or in the water.  My two favorite beaches are Elbow Beach, Bermuda and Skaket Beach in Orleans Maand my favorite water sport is paddleboarding or SUP.

In class the question was posed; does water drain from a sink in a clockwise or counterclockwise direction?  A non-scientific experiment was carried out using a bathroom sink.  The water faucet and drain both appeared to be centered on the sink.  A hand was pressed tightly against the drain and was used as a stopper until the sink was half full of water, and then removed to observe the flow of water.  The direction was not immediately obvious so a small piece of paper was tossed in and a counterclockwise flow was observed.

According to Everyday Mysteries the flow direction of draining water in toilets, sinks and hurricanes depends upon which hemisphere you’re in. This phenomenon is called the Coriolis force. “The Coriolis force is caused by the earth’s rotation. It is responsible for air being pulled to the right (counterclockwise) in the Northern Hemisphere and to the left (clockwise) in the Southern Hemisphere.However,, according to Snopes .com, the Coriolis force does not affect your sink or bathtub as the CF affects large scale measure for things like “1000 meter cyclone”2  And the water flow in the sink or tub has more to do with plumbing and the shape of the vessel and how level it is and less to do with the Coriolis Force”  “The direction of rotation in draining sinks and toilets is NOT determined by the rotation of the Earth, but by rotation that was introduced earlier when it was being filled or subsequently being disturbed (say by washing). The rotation of the Earth does influence the direction of rotation of large weather systems and large vortices in the oceans, for these are very long-lived phenomena and so allow the very weak Coriolis force to produce a significant effect, with time.“3  I like the Northern/Southern hemisphere argument but is was unable to cull a  concrete opinion from the web.


1 comment:

Bruce Berman said...

Deb - Very nice work
Please label your post with your name.