Two men on opposite sides of the world appear to have solved one of the biggest scientific questions of our time.
No, it's not, "What has four legs, and ticks?" It's whether water drains in the opposite direction in the Southern Hemisphere.
One of the funniest "Simpsons" episodes of all time has Bart trying to prove Lisa wrong when she says that water drains in opposite directions in the Northern and Southern Hemispheres.
She said it was because of the "Coriolis effect," a force that makes winds flow in one direction north of the equator, and another south of it.
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Over the years, many attempts have been made to answer the question of which way water flows ... with varying results.
The shows made synchronized YouTube videos that demonstrate how water drains in Huntsville, Ala. and Sydney, Australia.
(To sync them, play the video on the left up to the point where it says, "synchronize videos." Then start playing the other one. Once that video shows "synchronize videos," play the other vid once more where you paused it.)
SmarterEveryDay's Destin Sandlin and Veritasium's Derek Muller didn't just stop at flushing toilets or watching water flow down drains.
They both filled kiddie pools full of water and then drained them, putting food colouring in each to see how the water flows out.
Sure enough, they proved Lisa Simpson's theory. The water in Alabama flowed counter-clockwise, and in Australia it drained out in a clockwise direction.
Now, if only we could apply this kind of scientific rigour to other questions.
Like, are we alone in the universe?
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