Does water really spin counterclockwise below the equator or is that just a myth? Thank you?
415347
Yes, I asked my sister to check it out when she emigrated to Oz
407244
The idea that the water rotates one way in one hemisphere and the other way in the other hemisphere is a myth.
1065217
If you are referring to the phenomenon of water actually flowing "uphill"- it is only a myth.\n\nMany have thought themselves to observe such a thing but it is only an optical illusion. Usually the result of objects just below the surface causing a questionable rippling effect that makes the water appear to flow the "wrong" way.\n\nIt's neat to watch though.
433088
The coriolis effect is the effect on the flow of fluids due to the earth's rotation. Because fluids (liquids and gasses) experience very little frictional force with any surface that it is in contact with, as the earths spins, the fluids tend to lag behind and appear to spin.\n\nThis is mosy noticable in Hurricanes. Note that all the hurricanes abov the equator spin in the same direction.
789602
It's also true with water going down the drain. It goes the other way in the southern hemisphere, because of the earths rotation.
161441
As the water starts to circle, it is thrown to the outside, due to centrifugal force (to be more accurate, the force that it experiences is centripetal force=(mv^2)/r since centrifugal force is a so-called fictitious force). As it's thrown outside, it starts to move faster (when things move in a circle, the things that are nearer the outside move faster than things near the center; you can see this if you have a "old-fashioned" record player by putting two coins on it, one near the center and one near the outer edge and trace how long it takes them to complete the lengths of their paths). So the circling water near the outer rim is moving very fast and experiences bigger forces (since the force is proportional to velocity). But the water near the middle is moving slower because it's being dragged along the bottom and so ends up slowing down much more. Since the water near the bottom is moving so slowly, it exhibits a much lower centrifugal force and so there is little to no centrifugal force near the bottom (or middle). This is why you have a whirlpool (vortex): the water near the top is pushed out more (since there's higher centrifugal force there) and the water near the bottom is hardly pushed outward at all (since there's lower centrifugal force near the bottom to push it out).
1137413
Good grief. Four answerers and the original asker have all bought into a proven urban legend.\n\nIT ISN'T TRUE PEOPLE.\n\nWater will go down either way no matter where you are.\n\nThe twisting effect of the Coriolis force is real and does influence certain large things like the movement of air masses, but the effect is so small that it plays no role in determining the direction in which water rotates as it exits from a draining sink or toilet. The Coriolis effect produces a measurable effect over huge distances and long periods of time, neither of which applies to your bathroom. Toilets and sinks drain in the directions they do because of the way water is directed into them or pulled from them. If water enters in a swirling motion (as it does when a toilet is flushed, for example), the water will exit in that same swirling pattern; as well, most basins have irregular surfaces and are not perfectly level, factors which influence the direction in which water spirals down their drains. The configuration of taps and drains is responsible for the direction of spin given to water draining from sinks and bathtubs to a degree that overwhelms the slight influence of the Coriolis force.\n\nThe belief that the Coriolis force influences the direction in which water drains from plumbing fixtures is widespread and has been repeated as fact in a number of venues, including popular television shows (such as world traveler Michael Palin's Pole to Pole) and even in textbooks. We can only speculate on why people are so enamored of this snippet of misinformation, guessing that it has something to do with the desire to find some of the mysteries of science in the realm of the everyday.
101455
>>>>>at 4 degrees above its freezing point, water sinks.\n\nThis is true.\n\n>>>>any lower, and it begins to freeze, forms crystals, and floats.\n\nThis is not true. Water begins to freeze at 0oC, not at 3.9oC or even 1oC.\n\n>>>>any warmer, and the molucular action makes it less >>>>dense.\n\nThis is not true. Water becomes less dense at warmer temperatures due to kinetic motion impeding the formation of hydrogen BETWEEN molecules.
282404
In the northern hemisphere the toilet bowl water circulates counterclockwise, and in the southern hemisphere it circulates clockwise.\nThe water in the toilet moves in the same manner as the air in a hurricane or tornado. The effect causing the rotation is the Coriolis effect, and is not a force, although it is sometimes referred to as a force.\n\nConsider the situation in the northern hemisphere.\n\nLiquids or gases nearer the equator are traveling faster as the earth turns than the liquids and gases nearer the poles, because everything nearer the equator must travel a longer linear distance each day to make the 360 degree rotation from west to east. If liquid/gas nearer the equator must head toward a target (low pressure) in the direction of the poles, it finds that the target is not traveling as fast west to east as it (liquid/gas) is traveling, and if it stays on its direct polar-bound route it will overshoot the target to the east (right on a map). To hit the target the liquid/gas must correct its flight and turn west (left) as it travels poleward. Such corrective action creates a curved path of travel which leads to circular flow. Liquid/gas poleward of the target (low pressure) is traveling west to east slower than the target (the diameter of the earth measured perpendicular to the earth rotation axis decreases as one moves toward the poles), and in its travel towards the equator, will undershoot the target to the west(the target moved faster). To reach the target from the pole side the liquid/gas must turn to the east in a curved path, and this leads to circular flow in the same counterclockwise direction as the liquid/gas coming from the other side of the target (low pressure).\n\nIn the southern hemisphere the case is the same, but because poleward bound and turning west means circling clockwise, as does equator-bound and turning east.\n\nNow in a toilet bowl the target and low pressure is the drain (a sink hole), so the drain operates the same as a hurricane. Ditto for the tornado.
1140075
You raise an excellent question because coriolis forces caused by the direction of the eye with respect to the spin of the earth are very important in organizing the storm and its direction of rotation and natural rotation is reversed on opposite sides of the equator.  However, hurricanes have been known to stall or even reverse direction before continuing.  The hurricanes take enormous quantities of heat from the warm sea water and build up organized momentum that may have a life all its own.  When you let water out of bath tubs, there is a natural force (coriolis) that spins the whirlpools in opposite directions north and south of the equator; but you can start the whirlpool in the wrong direction buy hand and it will continue due to momentum.
227951
Contrary to legend, it depends on the sink - not the hemisphere. The Coriolis force (which makes large scale currents and weather patterns turn clockwise in the Northern hemisphere and counter-clockwise in the Southern hemisphere) is really too small to matter in a sink/toilet. The geometry of the sink and the motion of the water before you pull the plug plays a much larger role.
223771
This is not true, but widely circulated as fact.\n\nI quote verbatim from snopes:\n\n"Because  \n\n   the Earth is a globe spinning on an invisible axis, a point at its equator will make a circuit of 25,000 miles in the space of a day, but any point not on the equator will make a shorter round trip; the closer that point is to either of the poles, the shorter its trip will be. Put another way, a pencil     at the equator travels 1,030 miles an hour, whereas another at Sarasota, Florida, moves at 930 miles per hour, and one at the North pole doesn't move at all. \n\n This apparent difference in speed results in the Coriolis force, an effect that imparts a twist to largish events happening away from the equator. Best known is its effect on air masses: as they move away from the equator, their speed (which matches that of where they started from) appears to be faster than that of the surface over which they are traveling. This sets them turning in a clockwise twist in the northern hemisphere and a counterclockwise twist in the southern. (Before you complain we have that backwards, please click here.)  Likewise, a cannonball fired due north will veer a teeny bit to the east, and one fired to the south will deflect ever so slightly to the west, something a skilled gunner would make an adjustment for. \n\n The twisting effect of the Coriolis force is real and does influence certain large things like the movement of air masses, but the effect is so small that it plays no role in determining the direction in which water rotates as it exits from a draining sink or toilet. The Coriolis effect produces a measurable effect over huge distances and long periods of time, neither of which applies to your bathroom. Toilets and sinks drain in the directions they do because of the way water is directed into them or pulled from them. If water enters in a swirling motion (as it does when a toilet is flushed, for example), the water will exit in that same swirling pattern; as well, most basins have irregular surfaces and are not perfectly level, factors which influence the direction in which water spirals down their drains. The configuration of taps and drains is responsible for the direction of spin given to water draining from sinks and bathtubs to a degree that overwhelms the slight influence of the Coriolis force. \n\n The belief that the Coriolis force influences the direction in which water drains from plumbing fixtures is widespread and has been repeated as fact in a number of venues, including popular television shows (such as world traveler Michael Palin's Pole to Pole) and even in textbooks.  We can only speculate on why people are so enamored of this snippet of misinformation, guessing that it has something to do with the desire to find some of the mysteries of science in the realm of the everyday. "
728543
From USA Today:\n\n"Q: Why does most of our weather come from the west if the Earth is rotating the opposite way?\n\nA: When looking down at the North Pole, the Earth spins counterclockwise around its axis. A point on the equator travels at about 1,100 mph, while a point directly at the poles does not move at all. An apparent force called the Coriolis force results from this difference in speeds, deflecting objects to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. The Coriolis force, combined with solar heating patterns across the Earth, create distinctive wind patterns that drive weather systems.\n\nOne prevailing surface wind pattern that results is located in the mid-latitudes, between 30 and 60° North. Solar heating alone, without the Earth's rotation, would produce prevailing southerly winds. The Coriolis force, however, deflects these winds to the right, creating prevailing winds out of the west and southwest (the westerlies). \n\nSolar heating patterns in the tropics, from the equator to about 30° North, combined with the Coriolis force, produce weak prevailing winds out of the east (the easterlies). Southern regions of the USA, including Florida, are affected by the westerlies at times and the easterlies at others."\n\nHope this helps explain it. Check the first link for other weather questions and second link to see a full explanation of the consequences of rotation on weather.
68065
It's due to the rotation of the Earth - specifically the Coriolis Effect. See http://answers.yahoo.com/search/search_result?p=Coriolis+Effect\n\nMy answer assumes you have a circular toilet which drains right down the middle and recieves no directional impulse from the water flowing in ;-). ie. Under strict controlled conditions, you can make water spin in opposite directions as it drains through a hole.
1122646
NO!  Normally yes, but right up near the MAGNETIC north OR the magnetic South, it varies.\n\nIf you are between the true north and the magnetic North, the end of the other needle can spin or point to the true North.
228929
Yes.  \n(1) The centripetal force due to rotation is greatest at the equator and vanishes near the poles.  Things literally weight more at the poles than the equator.  Rockets carrying satellites are typically launched from equatorial regions because it takes less fuel.\n\n(2) The coriolis (sp?) effect results from Earth's rotation.  Something moving in a straight line has the Earth turn out from underneath it.  This makes hurricaines spin in their respective directions in the northern or southern hemisphere.  Also, a "good" pendulum will seem to rotate it's swing over 24 hours.  It's going the same way - the Earth turns beneath it.
414354
In the Northern Hemisphere, a tornado or twister twists counter-clockwise. In the Southern Hemisphere is clockwise. This is due to the Coriolis effect, caused when objects (in this case air) moves over the rotating earth. The air flows towards the twister, but curves to right (relative to the direction it is flowing). It is easier to visualize if you think about some air flowing straight north to a twister. Since the earth's surface is moving faster towards the east where it started, it carry on some of the momentum and curve to the east (right of the northerly direction it was flowing). This will tend to cause the air to miss the twister, but he extreme low pressure will allow the higher pressure around it to bend the flow towards the funnel, but the air will have the angular momentum of moving the right as it moves in, thus creating the counter-clockwise twist. In the Southern Hemisphere, a flow from the south towards a twister will be coming from a place closer to the earth's axis, and thus will be moving East more slowly than the land under the twister, so it fall behind (to the West) as it approaches, resulting, through the similar process as described above, in a clockwise twist.