TRIVIAL PURSUITS: Does water in a sink or toilet rotate differently in the Northern versus Southern Hemispheres?

Is it true that drainage of water in a sink or toilet rotates differently in the Northern versus Southern Hemispheres?

This proposition is false. An influence called the Coriolis Effect is the inertial force that deflects an object, such as air masses, moving about Earth. While it influences the motion of ocean currents and air masses in the atmosphere, it has a negligible effect on the drainage of water in toilets, bathtubs and sinks.

What determines the direction of drainage is principally the shape of the basin and the direction from which it is filled.

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