What physics effects work to make these ripples? Thanks, i need an answer quick.
213575
I hope this helps.\n\nAsk A Scientist\nPhysics Archive  \n\n--------------------------------------------------------------------------------\n\nRipples in Water \n\n10/29/2004 \n\n \nname         Susanne H.\nstatus       educator\nage          50s\n\nQuestion -   What is the scientific explanation of how a ripple is\nformed when something is dropped onto water?  Why not just one wave?\n-----------------------------------------------------------------------\nThe ripple effect is similar to a spring. Unless a spring is carefully\n"damped" the weight on the end of a spring will oscillate up and down. A\nsimilar thing happens when a weight is dropped into a pool of liquid. The\nweight "pushes" the liquid down, but because the liquid has been displaced\nfrom its equilibrium point it recoils back up. The exchange of potential\nand kinetic energy back and forth causes a ripple in the liquids surface\nback and forth until friction causes the waves to decrease in amplitude.\n\nVince Calder\n=====================================================\nDear Susanne,\n\nThe train of ripples is caused by the oscillation of the water at the point\nthe stone is dropped.  Initially, the stone depresses the water under it.\nThe depressed water is then lifted by the buoyancy of the water around it.\nSince the top of the depressed water is under the top surface of the rest of\nthe water, the buoyant force on it is greater than its weight and so the\nwater is rapidly accelerated upwards.  When it reaches its original level\n(lined up with the top of the rest of the water), it is moving upward and\nwill continue some distance above the rest of the water.  Eventually, of\ncourse, its unsupported weight causes it to stop and start falling down.  It\nwill again overshoot its equilibrium position and continue downward some\ndistance. This oscillation continues until the energy lost to the viscosity\nof the water finally brings it to rest in its original position.\n\nThe up and down oscillations of the water which was originally under the\nstone cause the waves to form which propagate outwards in a circular\nfashion.\n\nBest, Dick Plano...\n=====================================================\n\n\n\n--------------------------------------------------------------------------------\n\n  Back to Physics Ask A Scientist Index \nNEWTON Homepage Ask A Question \n\n\n\nNEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators.\nArgonne National Laboratory, Division of Educational Programs, Harold Myron, Ph.D., Division Director.
101063
i believe it is refraction, the ridges bend the light into certain colours.  like the rainbow effect in a prism.
491970
Someone posted the exact same set of questions a few days back, either here or on the physics page - you ought to be able to find the methods in the responses. Have a look.\n\n\nBest of Luck - Mike
202034
It's not a gimmick, it's an illusion , the same as the mtatlic hill, you're going down but it looks lie uoi are going backwards,something to do with physics, ask the physic' pro's for the deep, lengthy answer, they're good!
41273
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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They're actually not perfect.\n\nBut check this link out:\n\nhttp://www.pa.msu.edu/~sciencet/ask_st/031198.html\n\nAnd this:\n\nhttp://www.sciam.com/askexpert_question.cfm?articleID=000D93E1-778C-1C72-9EB7809EC588F2D7&catID=3\n\nThey retain a spherical shape because of gravity.
199729
There is a dent, although it is quite small and also short-lived. The air pressure just in front of the falling drop pushes the surface down just before the drop hits.\n\nBuh-bye now.
387755
We did something like this in my physics lab with an Atwood machine.  It was a pully with weights hanging from it.  I can't exactly remember how it worked, but maybe this will inspire you.  We also did something with an air track and these two masses colliding and we'd see which one would go in which diretcion.  You need a nearly frictionless surface, like an air hockey table or ice slab.
42909
Post it in physics. However, if it is very flaky, post it in philosophy or spirituality or religion.
407978
With or without gravity, there are two types of friction, static friction from the current and voltage and kinetic friction of the projectile as it travels down the rails. The kinetic friction mainly comes from the projectile "scraping" across the rails. This results in rail erosion when firing, ejection would produce hot plasma and damaged rails. \n\nThus, gravity has little or no effect, unless you position your rails such that the projectile is resting on one of the rails, increasing the kinetic friction. This problem is resolved by experimenters, who put the projectile side by side with the rails.\n\n        []o[] <---- Cross-section of rails with a projectile in between\n\nOf course, the spacing in between the rails and the projectile yet again must be very close, so even if there was a region of zero gravity, it would be hard for it to shift.\n\nReduction of friction, at most, is a good rail surface, often polished for a long time and a well-shaped projectile. To help with the acceleration and speed of the projectile, and slightly reducing rail erosion by eliminating some skin friction, gas injections are also used to first push the projectile then quickly fired together with the voltage.
112600
<LOL> NO! The doppler effect is about compression and rarifaction of a wave generated by a source moving through space. Time can only change with a warping of spacetime itself. Apples and oranges.
321464
It may be surface tension.
449013
there is an optical effect like this ( it is just a refraction at an interface - like water and air ) and sorry i can't remember either ( i will search tho )\n\ncool i searched the term ATMOSPHERIC REFRACTION and guess what LOL( go to Wikipedia )
296189
How refreshing. Someone with a credible degree asking an honest question on these teenager boards.\n\nGoogle it and use your engineering brain to come to a conclusion.
489517
I know the answer is in my basic physics book.  I would have to look it up.  You should too.
363999
I am not really sure why but the guys on Myth Busters did this experiment on their show on the Discovery Channel. There is a little blurb here: http://dsc.discovery.com/fansites/mythbusters/episode/episode_02.html\nand more info on the experiment here:\nhttp://www.eepybird.com/science1.html\nhope that helps with your science fair project! good luck!
636800
Gravity waves have a frequency.  That's a good point about destructive interference.  I hadn't thought about that.  However, from what I understand, there should be gravity waves generated by two co-orbiting large bodies.  If you think about it, their gravity would increase and decrease if that was the case, but always remain far above zero.  So....if you could cancel it with a gravity wave generated by another source that was identical and just out-of-phase, you should still have a baseline gravity that was nonzero.  \n       In other words, no negative gravity (that I know of) so when it cancels, it's not zero.