A ship bobbing in the sea ( Moving up and down)..is it SHM? Assuming its stationary.?
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This is a classic problem from hydrodynamics textbooks. The short answer is, it is approximately simple harmonic motion. You can compute the restoring force caused by the displacement of the liquid if you depress a floating boat (Archimedes principle) and that then, balanced with the weight of the boat, creates the conditions for simple harmonic motion. You can approximate the period and amplitude of motion etc. \n\nHowever it gets more complicated than this of course:\n\na. There are damping forces caused by the motion of the boat through the water and the air\n\nb. The water is not completely incompressible, and the density of the water varies some with depth (a tiny effect)\n\nc. There are surface tension effects and entrainment effects\n\nd. The motion of the boat will be more complicated than simple linear motion in one dimension\n\ne. There will probably be deformation effects on the boat, changing its shape\n\nf. gravity is not constant as the boat is moving up and down a small distance in a gravity gradient\n\nand so on. \n\nHowever, the REASON that sines and cosines are so prevalent everywhere in physics is because simple harmonic motion is such a good approximation for so many things. \n\nWhy is this?\n\nWell consider Newton's Second law: F=ma, where F is force, m is mass and a is acceleration. Newton's second law is not always true, in the quantum world and in relativistic situations, but it is true under many conditions, so it is a good place to start. \n\nIn general, the force F will be some sort of nonlinear function of position x:\n\nF=F(x)\n\nHowever, if x is small, then we can approximate F(x) by a McLaurin series:\n\nF ~ F(0) + x F'(0) + h.o.t. \n\n(h.o.t. is a common acronym for higher order terms).\n\nThis then produces the equation for simple harmonic motion, when substituted into Newton's 2nd law:\n\nF(0) + xF'(0) = m d/dt(d/dt(x))\n\nMany other equations in physics like Schrodinger's equation, or wave equations with forcing, or the heat equation, or the inhomogeneous Laplace's equation include 2nd order derivatives, and can similarly be put in some form where simple harmonic motion is the result. So as strange as it seems when you are just learning about SHM in physics, it really is everywhere in all kinds of unexpected places! \n\n\nOne of my favorites is the waves of heat and cold that are travelling down into the earth from the seasonal forcing produced at the surface. Drilling down, one can observe these waves of hot and cold (with some diffusion) going back many years.
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Hi,\n\nGalileo was faced by similar queries and this is his response:\n\nShut yourself up with some friend in the main cabin below decks on some large ship, and have with you there some flies, butterflies, and other small flying animals. Have a large bowl of water with some fish in it; hang up a bottle that empties drop by drop into a wide vessel beneath it. With the ship standing still, observe carefully how the little animals fly with equal speed to all sides of the cabin. The fish swim indifferently in all directions; the drops fall into the vessel beneath; and, in throwing something to your friend, you need throw it no more strongly in one direction than another, the distances being equal; jumping with your feet together, you pass equal spaces in every direction. When you have observed all these things carefully (though there is no doubt that when the ship is standing still everything must happen in this way), have the ship proceed with any speed you like, so long as the motion is uniform and not fluctuating this way and that. You will discover not the least change in all the effects named, nor could you tell from any of them whether the ship was moving or standing still. In jumping, you will pass on the floor the same spaces as before, nor will you make larger jumps toward the stern than toward the prow even though the ship is moving quite rapidly, despite the fact that during the time that you are in the air the floor under you will be going in a direction opposite to your jump. In throwing something to your companion, you will need no more force to get it to him whether he is in the direction of the bow or the stern, with yourself situated opposite. The droplets will fall as before into the vessel beneath without dropping toward the stern, although while the drops are in the air the ship runs many spans. The fish in their water will swim toward the front of their bowl with no more effort than toward the back, and will go with equal ease to bait placed anywhere around the edges of the bowl. Finally the butterflies and flies will continue their flights indifferently toward every side, nor will it ever happen that they are concentrated toward the stern, as if tired out from keeping up with the course of the ship, from which they will have been separated during long intervals by keeping themselves in the air. And if smoke is made by burning some incense, it will be seen going up in the form of a little cloud, remaining still and moving no more toward one side than the other. The cause of all these correspondences of effects is the fact that the ship's motion is common to all the things contained in it, and to the air also. That is why I said you should be below decks; for if this took place above in the open air, which would not follow the course of the ship, more or less noticeable differences would be seen in some of the effects noted.\n\nAlthough, this seems obvious to us now in its day it was quite startling. But it is the same for an Astronaut on a space walk. His craft appears stationary to him, although both he and it a traveling at great speed. So, we judge that something is moving only by its movement relative to us or some other object.\n\nThis, if you like, is Galilean relativity, we judge objects to be moving only if they are moving relative to our frame of reference.
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first of all it wont look too good... thats a lot of pee!!! next, they must  have on water proff  clothing, it will be all over then. lastly, the terminal velocity is -2... they are pissing against the wind! thank God they have enough sense to be strapped down, otherwise youll have a lot of chooped  hambugger to deal with
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First of all, IT'S GRAVITY BABY! Not really, but it does play a part. It's mostly the force of the wave, working with gravity to move that board at that certain speed.\nsomewhat like that
675436
It exists, but there's no real mystery about it anymore. The main theory is that it's just pockets of methane gas under the ocean floor. When the gas escapes, it lowers he density of the water big time and any ship caught in it's path will sink almost instantaneously, it also messes with plane engines if enough of it enters the air in dense enough pockets.
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definitely not true. it just appears that way because it hits the water and disperses before you can really notice it but if you watch its there.
57676
Approximately, circular motion, alive
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I assume you are talking about any wave equation, not just a QM probability density function.\n\nIn any case, what do you mean that you have a "different x for every instant t"?  That is not the case.  I suspect you are thinking of travelling along with the crest or trough of a wave.  As t changes, the location of the crest and trough changes, but that is not the only location on the wave.\n\nWhat the wave equation specifies is the magnitude of the wave at *any* location x, at any time t.  So, if you are at a constant location x', the magnitude of the wave will vary periodically in time at that location. If you were a cork on the water, you would bob up and down at your location as the waves passed you. But similarly, if we were to somehow freeze time, and travel up and down our x axis, the magnitude of the wave would vary periodically in space as well.  So now, rather than a cork bobbing on the water, imagine you're on a jet ski that is going across the water so fast, compared to the speed of the waves, that it's almost like the waves aren't moving.  Yet you bob up and down as you cross the waves that lie in your path in space.\n\nHence, the wave varies both in x and t, independently.
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It is said that the SHIP sinks in the water in that area.\nThat's may be due to higher gravity or some other force which is still unknown.
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Because a ship has surface area, a needle doesn't. Water can flow around it, so it sinks.
555212
Yes, velocity is changing it's direction as well as magnitude. Acceleration due to gravity is acting downward.
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Sound travels in a wave.  Actually travels best through a solid.
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Sometimes, rocking the boat is the only way to get attention. Sometimes the boat needs to change course because it's heading for dangerous waters. \n\nOne analogy about stability doesn't meant that things are better when stable.
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well um, there would have to be more info to solve this. if it is directly horizontal from you, then the ship could be infinite distance from you (or as far as u can see).
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You have uncovered one of the secrets of the universe. Simple Harmonic Motion (SHM) surrounds us in every aspect of the universe. It is the lowest common denominator. Even Newton got it slightly wrong in his First Law where he said that a body will continue in uniform motion until an external force acts upon it. There is nowhere in the known universe that gravity does not exist.\n\nConsider an air table which is flat and which extends in all directions by a million miles, and it rests on the earth. place a puck on it and give it a gentle nudge. It will move off in the direction you push it at an apparently constant velocity, however it will eventually stop and return to the point where it started because of the earth's gravitational field. It will shoot past and head off in the opposite direction until it stops again, being pulled back by the earth's gravitational field. It will continue this way forever (ignoring all friction), oscillating in simple harmonic motion. \n\nNewton's problem was that he was restricted to observing a very small portion of the SHM path, so it seemed linear.\n\nAnyway, congratulations, you are on the path to unlocking the secrets of the universe.
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TO make sure there is no BUGS/Glitches in the software its like when u build a boat ... gotta make sure it floats before sending it out to sea
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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 :)