Wednesday, July 28, 2010

Water Experiment: The Drain Dilemia

Drain question: Experiment 1

For our first “assignment” the class was taken, as most of you reading this know, to a women’s bathroom to observe what way the water spun down the drain (in both a toilet and a sink). When my group observed both the toilet and the sink drain, the majority came to the conclusion that the water spun clockwise.

Personally, that is what I observed as well. The toilet was a little bit trickier to tell the direction, but after looking at it closely, clockwise, was my final answer.

As part of this assignment, the class was to research the answer and come a conclusion based on fact. Rolled into this, was the assignment to see if toilets in Australia drain water in a different direction than Boston.

The Coriolis force, "An apparent force that as a result of the earth’s rotation deflects moving objects ( as projectiles or air currents) to the right in the northern hemisphere and to the left in the southern hemisphere,” as defined by Merriam Webster, was applied by some as an explanation to why certain drains drain water in different directions.

After researching, I am sticking with my original theory of which direction the water spins. Although some people use the Coriolis effect to explain, for instance, why toilets may flush differently in Australia, after researching, this theory has been debunked numerous times. One website that I came across described it very well stating, " The Corlious effect is much too weak to have any affect on small, short-lived rotating bodies of water under normal conditions" ( After researching, I have found that the reason that toilets and drains flush in different directions depends on the shape, size, and overall design of the drain.

- Hilary Katulak

No comments: