What is the coriolis effect?
359374
The Coriolis effect is an apparent deflection of a moving object in a rotating frame of reference. There are examples of this effect in everyday life, such as the direction of rotation of cyclones. Due to the effect, cyclones rotate counterclockwise in the northern hemisphere, and clockwise in the southern hemisphere. However, contrary to popular opinion, it has no noticeable effect on the rotation of water in draining sinks and toilets (see the toilets/bathtubs section below). The effect is named after Gaspard-Gustave Coriolis, a French scientist, who described it in 1835, though the mathematics appeared in the tidal equations of Laplace in 1778.
1009751
Sunlight heats parts of the atmosphere, other parts remain cold.  This causes pressure differences, and these pressure differences cause a force to be applied to neighbouring air.\n\nGravity also acts upon the air.  \n\nThe earth's rotation causes a drag force on the layer of air touching it.  \n\nEver heard of the coreolis effect?\nhttp://en.wikipedia.org/wiki/Coriolis_effect\n\nI imagine there are other forces too, like internal shear friction, large objects causing wind deflection, the list is probably endless.
741307
Episodes of the Simpsons and urban legend have it that the spin of flushed water is determined by the hemisphere one is in, presumably because cyclones, hurriances, and other large-scale forces of nature spin in opposite directions in opposite hemispheres.\n\nUnfortunately the force that makes hurricanes and cyclones spin in opposite directions (the Coriolis force) operates on a very large scale, over thousands of miles in fact. The forces that determine whether the toilet flushes clockwise or counter-clockwise are a function of the toilet, no more, no less. The Coriolis force does not operate on such small scales as the whole manifestation of its effect is seen due to the difference in rotation between two points on Earth that are far apart.\n\nSo the answer to your question is "Depends on the toilet", nothing else.
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.
572689
No easily measurable effect. There is a small Coriolis effect when flying north or south, but not when flying east or west. The air and Earth are all rotating as a unit, so except for wind, it is no different than driving on the ground. Wind speed and direction is controlled more by heating from the Sun than anything else, and it can blow in any direction. True, prevailing winds to tend to make for quicker travel in one direction, but that is not what you are talking about I think.
763595
It doesn't make a difference. While the Coriolis effect does make hurricanes turn anti-clockwise in the northern hemisphere and clockwise in the southern, that's because hurricanes are such huge, slow-forming systems.\n\nFlushes (and sinks for that matter) are way too small for the same effect - the direction of your flush is simply dependent on how the toilet is manufactured. The force of the Coriolis effect is really small compared to the force of the rushing water in your toilet or sink.
307489
It's because of something called the Coriolis effect, which is due to the earth's rotation. (First reference).  The basic idea is that, because the earth is rotating fastest at the equator, things moving north or south feel a slight deflection to the west or east.\n\nAir spirals into the center of a hurricane. So, imagine a lump of air that starts to the north of the hurricane's center. As that air moves south, it's going to enter areas where the earth is moving slightly faster. Since the earth spins toward the east, this lump of air will fall behind slightly, and, from our point of view, move towards the west.  A lump of air starting on the south of the hurricane, sees the reverse: it moves north, and is thus moving slightly faster to the east than the hurricane center. \n\nIn the southern hemisphere, this is reversed, and cyclones there spin clockwise.
25693
Down. Clockwise or anti-clockwise rotation is very much dependent on the first impulse when you open the drain, with coriolis force a distant second.
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.
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.
373244
clockwise in the northern hemisphere, anticlockwise in the southern. this according to the coriolis force, but of course there otehr factors that might influence the direction of the water (geometry of the sink, external vibrations, you turning your finger in water....)
750556
While the question/answer below is about weather, the information is the same for just wind.\n\nQ: 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. \n\nSource(s):\nhttp://www.usatoday.com/weather/resource...\nhttp://csep10.phys.utk.edu/astr161/lect/...
24112
The short answer is that toilets flush to the shape of the toilet - not because of northern or southern hemisphere location\n\nThe longer answer is that in theory it is possible that the "Coriolis effect" will change the the rotation of the flush. The Wikipedia link below has a detailed analysis. It can be abbreviated to "it's possible in an exact, scientific, controlled environment"
240419
It should flow counterclockwise because of the Coriolis effect.\n\nHowever:\n\n>> But, the Coriolis force is very small, indeed. \n \nCompared to the rotations that one usually sees (tires on a travelling automobile, a compact disc playing music, or a draining sink), the rotation of the Earth is very small: only one rotation per day. The water in a sink might make a rotation in a few seconds and so have a rotation rate ten thousand times higher than that of the Earth. It should not be surprising, therefore, to learn that the Coriolis force is orders of magnitude smaller than any of the forces involved in these everyday spinning things. The Coriolis force is so small, that it plays no role in determining the direction of rotation of a draining sink anymore than it does the direction of a spinning CD. \n\nThe direction of rotation of a draining sink is determined by the way it was filled, or by vortices introduced while washing. The magnitude of these rotations may be small, but they are nevertheless gargantuan by comparison to the rotation of the Earth. I decided to include a picture of a draining sink, and the first one I tried in my house was found to drain clockwise (the opposite of what the silly assertions would have it do here in the northern hemisphere). This direction was determined entirely by the way the tap filled the sink. The direction of rotation of a draining toilet is determined by the way the water just under the rim is squirted into the bowl when it is flushed.<<\n\nI guess you'll just have to observe - I have made the water in kitchen sinks swirl the "wrong" way just for the heck of it, and it doesn't begin to immediately go the "right" way unless I act on it.
1152346
It has EVERYTHING to do with climate, season, winds, etc.\n\nThe Coriolis effect, which results from the Earth’s rotation, plays an important role in large-scale circulation of the atmosphere. As viewed by an observer on Earth, air appears to be deflected to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. This results in areas of low pressure rotating counterclockwise in the Northern Hemisphere and clockwise in the Southern hemisphere, with the opposite being true for areas of high pressure. If the Earth’s rotation were to suddenly reverse itself, these patterns would also be reversed. The westerlies would become easterlies and the northeast trades would blow from the northwest. \n\nChanges in the Earth’s rotation would have an effect on ocean currents, which can influence local climates. The El Niño and La Niña phenomena that affect global climate patterns on a periodic basis. \n\nOne large component of a location’s climate that would not likely be affected would be the effect of seasons, which are more dependent on the tilt of the Earth’s axis than they are on the Earth’s rotation.
97237
Coriollis force theory indeed\n\n\nCounter clockwise winds travel around a LOW pressure area,upward.. Winds around a High pressure area travel clockwise downward in the Northern hemisphere.....
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.