On the other hand, you wouldn't want to try to paddle through a large whirlpool in a row boat. Even small whirlpools are VERY powerful. While it may not suck a human being down into it, it is very likely that even an Olympic swimmer would soon tire trying to avoid it, and then risk drowning.
What direction does the water spin? Have you ever heard that water goes down a drain in different directions in the northern and southern hemisphere? Is it truth or myth? Technically, it is true. If there is no other outside force present such as the direction of the inflowing water, and the drain hole is perfectly level, water will rotate counterclockwise north of the equator and clockwise south of the equator.
You can find videos on YouTube and other places that claim to demonstrate the Coriolis Effect making water spin in opposite directions on either side of the equator. These demonstrations are for tourists You can learn more about the trick if you do a web search for "water equator test debunked". The Coriolis Effect is extremely slight, similar to the fact that we can stand on the earth without being knocked over by the 1, mile per hour speed of the rotating earth.
There are many forces that are stronger on a small body of water such as the angle of the drain, the slightest hand movement as you remove the plug, etc. In a natural setting such as a stream, there are usually other obstructions that create the spinning direction. If you were to stir water in the opposite direction of your hemispheric location, that is sufficient energy to create a vortex whirlpool since that stirring is a stronger localized influence than the slight rotational influence of the earth.
Some people even believe that water swirls down a toilet according to hemispheric influence. But that is NOT true. The direction of rotation in a toilet is caused by the direction of the water flowing into the toilet bowl from the outlets around the inside of the rim. What about a bathtub drain? Will the Coriolis-Effect be sufficient to influence the direction of the vortex? Only if the tub and drain are perfectly level, and the water is not disturbed when the drain plug is removed. But that is nearly impossible.
It is best to pull the plug with a chain rather than by reaching in with your hand. Your hand will cause slight currents as you put it into the water and then remove it, and that might be enough to influence the direction of the water. Pop Bottle Experiment. One of the most fun whirlpool experiments is with a pop bottle. You will probably spill water with this experiment, so it is best to do it outside or over a tub. Fill a 1-liter plastic pop bottle with water and turn it upside down.
Watch as the water fights to get out of the small opening. The fight is between water and air. If air doesn't replace the space occupied by the water, a vacuum will form and slow down the water while sucking the sides of the bottle in.
Notice the large bubbles of air climbing to the top of the water level. Many myths and legends of the sea have featured whirlpools, typically in situations involving great peril to shipping, and there are a number of famous whirlpools around the world which form consistently and frequently.
An especially powerful whirlpool is known as a maelstrom; one of the more notable maelstroms is the Moskstraumen, an immense network of eddies and whirlpools off the coast of Norway. Several things can lead to the formation of a whirlpool. Most commonly, whirlpools are caused by the meeting of opposing currents. When the currents are strong enough, they can start to wrap around each other, creating a spiral of rapidly swirling water.
Whirlpools can also be caused by winds, which may cause surface currents to switch direction, and consistent whirlpools are sometimes caused by geographical features which determine the flow of water currents in a region. Large ships are generally in no danger from whirlpools, although some reports from ancient history say otherwise.
It is thought that the mythical Charybdis of the Greeks may have been a whirlpool off the coast of Sicily, capable of swallowing small ships. Small boats and swimmers must use caution around whirlpools. As with any other current, the moving water can overpower a swimmer and pull him beneath the water, causing drowning.
A few whirlpools are large enough and powerful enough to merit our attention. These whirlpools are long-lasting, some having been on maps for centuries. Other notable whirlpools include the Old Sow Whirlpool near New Brunswick, Canada, which is said to make a sound similar to a pig, and the 16 mile per hour 26 kilometer per hour Naruto whirlpools off the coast of Japan.
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