how might a strong current make swimming dangerous?
84796
It can pull you far away from land.
703775
Yes , it is. And this from at least two view points:\n1) The salty marine water is a full of ions, so it represents  very clearly a electrolyte which is a conductive solution. All you need then is some electrodes which should have some differential potential in electronegativity. \n\n2)  The power of the waves which, there are already used as one of the alternative power producing  method. This is used either by actuating some radial turbines, or indirectly some kind of pistons actuated by some floating devices found on the surface of the water, in relative axial motion with respect to the fixed body of the piston. All of this devices are using the power of waves to actuate, then  directly, the generators. \n\nGood luck \nDfriend :)
153188
When you run amps of current through conductive water, such as salt sea water, the water will interact with a magnet.  The caterpillar drive which pumps water through a tube with a an electric field through the water and a moving magentic field to create a jet of water is actually possible.  The water, however, is only acted on by a magnet as long as the electric current is flowing.  When the electric current stops, the water is disorganized and is unaffected by a magnetic field.  (Water molecules, however, are slightly polar, being slightly positive on the 2 hydrogen on the end, and slightly negative on the oxygen end. Note that this is a STATIC electric field, not a magnetic field!!!!)\n\nForce=ExB.  The electric field crossed with a magnetic field creates force.  Similarly an copper wire is not a magenet either.  Yet when an electric current is flowing through it, and it intersects a changing magnetic field, it will create a force on the wire.  Also, a changing electric field in a wire will induce a changing magnetic field in a magnetic material, like iron.  \n\nBoy I hope I haven't muddied the waters;  let me summarize: water CAN support an electric field through it, and hence be acted on by a magnetic field.  Changing the electric field in water can induce a changing magnetic field in a magnetic material.  Water, in itself, IS NOT, and CANNOT be magnetic, ever.  If you put iron particles in it, the iron particles will be magnetic.  Other metallic salts, sodium, calcium and the like will NOT make the water magnetic, only conductive.
1109553
I don't know why, but USUALLY it slows enough while you are in water that it virtually stops. However, it doesn't always stop (trust me, been there). Your best bet if you are going swimming is to use a tampon. Better safe than sorry.
681885
It doesn't harm the baby but it is brilliant for the mother as the weight of the water takes the the weight of the baby off her back & internal organs.\n\n(don't forget the baby is swimming for the whole pregnancy anyway)
525583
What kills you is not the voltage but the amperes. Current (amps) = Voltage / Resistance. This is ohms law. 10mAmps causes muscular spasms. 30mAmps causes respiratory failure. 75 causes ventricular fibrilation that is the ineffective pumping of the heart. Until this point, the heart can gain back its normal rythym if a defilibrator is used. beyond 4amps, the heart stops functioning and beyond 5 amps, tissue in the body starts to burn.
803826
Very very dangerous. Potentially fatal.
658854
Well if you passed a large current through the ocean and you made the water a positive charge, and you threw in a magnetic asteroid rock that also had a positive charge it would not go into the water at all but shoot back into space or hover over the water depending on its weight and acceleration figure.! If the rock was heavy enough so that gravity outweighed the magnetic microcosmic charges between the rock and the ocean electromacnect fields would be surrounding the rock along with air, kinda like a mini lightning storm, or those glass balls with electricity inside and you put you fingers to and the electricity moves. Anyway when it does go down it will part the ocean so much so that not only would it be an bioscopic disaster for all beach dwelling bionic creature, it could also cause tidal waves, melting of the snow gaps and thus global warming, and a hole in the atmosphere. Im afraid the consequences of throwing that rock in would be devastating! Please Dont do it! And dont try it at home aswell! If you must go overseas and throw it in someone elses ocean! Heidi
277663
More or less the same kind of damage as if it hits land.\n\nEver done a belly-flop in the pool?  Imagine doing that at 150 mph.  The water is more or less solid at that speed.
976394
Seems to me like an accumulation of thousands of (young) fish, encountering plancton(food).\nOtherwise, it could have been the rising/falling tide, causing a whirlpool-like motion in the waters, which occur only once at that very same spot during the rise or fall of the tide, because of the constant changing water level. At falling tide, for example, if the water has to pass through a formation of rocks that are still submerged and invisible, the waters on the surface start to move noticeably, and if the trapped water body is large, it may create a scary scenario, which is indeed seriously dangerous for any swimmers caught in it.
797061
yes.  saltwater is salty, meaning it has a lot of ions.  Lots of ions conduct electricity.
749223
The flow of current is caused by an electric field being applied to a material if there are electrons which are not tightly bound to the atoms in the material. \n\nIn a metal, an electric field will apply enough force to the electrons to allow them to move from one atom to the next, as long as there is a free electron to replace it. The free electrons may come from a battery, or a loop of metal wire spinning in a magnetic field, for example. The bond of the electrons in the outer atomic shells to the nucleus is not so strong.\n\nOn the other hand, for an insulator, even very high electric fields will not encourage the electrons in the outer shells of the atoms to leave the atom. They are tightly bound to the nucleus.
1086668
since water is very dense, meaning very hard, yes sure. but it has to be coming at you at a great force or vise versa.(you coming at it really fast)
704271
No, unless they are at the water surface at the point of impact or a few feet away. The reason is that electrical charge weakens, (dissipates),  dramatically fast with distance, in the water.\nDan.
434607
1. Any water activity could result in drownings\n2. To windsurf you need some knowledge of sailing or you will be at the mercy of the wind. IE. how to tack into the wind\n3. The sail could trap you underwater or knock you unconscious.\n4. You are increasing your speeds (on a good day) to speeds that you would need safety equipment if you were traveling on land.\n5. It is dangerous to people around you. The board is being pushed by the wind and often hard to control. A wind surfer jumped a wave and landed on my friend when he was surfing. and the win
462329
http://www.oceansatlas.org/unatlas/issues/emergencies/OceanPhenHDNO/Dangerous.html
349738
i=v/r\n\ni=current\nv=voltage\nr=resistance\n\nThink of it as a hose full of water. The current is the amount of water going through the hose. The voltage would be the pressure of the water, and the resistance would be the diameter and the length of the hose. So obviously if you have a huge pressure on a huge diameter hose, you are going to have a huge current. But if your resistance is very high, like say the hose is just a little straw, then even with alot of pressure the current will be pretty small. And same thing the other way around. If you have a really big pipe, then you only need a little pressure to move alot of water.\n\nElecricity works the same way, except that resistance is not so much the wire as is the appliance in the circuit. So you might say that a light bulb has a certain resistance that causes a certain current when hooked up to a 12 volt power source.