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If the waves come from a localized source such as an earthquake or explosion, measurements at more than one location can be used to locate the source.
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If and waves
If the slowing down of certain seismic waves caused by the damp spot helped uncover the underground ocean, the unusual temperature variation with depth measured in 241 inactive oil wells helped locate the subterranean river.
If waves are emitted from an extended source, this can lead to incoherence in the transversal direction.
If the width of the slits is small enough ( less than the wavelength of the laser light ), the slits diffract the light into cylindrical waves.
If the waves are propagating through an anisotropic ( i. e., not rotationally symmetric ) medium, for example a crystal, then the phase velocity vector and group velocity vector may point in different directions.
If a spatial extra dimension is of radius R, the invariant mass of such standing waves would be M < sub > n </ sub > = nh / Rc with n an integer, h being Planck's constant and c the speed of light.
If the pump waves and the signal wave are superimposed in a medium with a non-zero χ < sup >( 3 )</ sup >, this produces a nonlinear polarization field:
If the pump beams E < sub > 1 </ sub > and E < sub > 2 </ sub > are plane ( counterpropagating ) waves, then:
If the pump waves are of frequency ω < sub > 1 </ sub >
If two waves of the same wavelength and frequency are in phase, both the wave crests and wave troughs align.
If two interacting waves meet at a point where they are in antiphase, then destructive interference will occur.
If the object is moving either toward or away from the transmitter, there is a slight equivalent change in the frequency of the radio waves, caused by the Doppler effect.
If electromagnetic waves traveling through one material meet another, having a very different dielectric constant or diamagnetic constant from the first,
If the diaphragm is placed on the patient, body sounds vibrate the diaphragm, creating acoustic pressure waves which travel up the tubing to the listener's ears.
If the bell is placed on the patient, the vibrations of the skin directly produce acoustic pressure waves traveling up to the listener's ears.
If a sound absorbing sheet is slid in between the prongs of a vibrating fork, reducing the waves reaching the ear from one prong, the volume heard will actually increase, due to a reduction of this cancellation.
If the waves have the correct frequency ( or wavelength ) and polarization, their energy can be transferred to the charged particles in the plasma, which in turn collide with other plasma particles, thus increasing the temperature of the bulk plasma.
If u is a superposition of such waves with weighting function φ, then
If scatterers are arranged symmetrically with a separation d, these spherical waves will be in sync ( add constructively ) only in directions where their path-length difference 2d sin θ equals an integer multiple of the wavelength λ.
If the distance between musicians is large enough, listeners may perceive waves to be out of phase.
If unobstructed, radio waves will travel in a straight line from the transmitter to the receiver.
If this depends on the polarization states of the waves, then their polarization may also be altered.
If the path length in the birefringent medium is sufficient, plane waves will exit the material with a significantly different propagation direction, due to refraction.
If the radio wave frequency is decreased, a point is reached where all waves ( even vertically incident waves ) are reflected back to the Earth.
If mounted on a finite baffle, and these out of phase waves allowed to interact, dipole peaks and nulls in the frequency response result.
If and come
If the bluff failed and they ran into trouble, Brannon had told the others, they would withdraw -- and he would come after his son another time.
If I don't come back in the house, Breed's going to '' --
`` If I don't come out within half an hour ride back to town and bring out a posse ''.
If our sincerity is granted, and it is granted, the discrepancy can only be explained by the fact that we have come to believe hearsay and legend about ourselves in preference to an understanding gained by earnest self-examination.
If Russian pupils have to take these languages, how come American students have a choice whether or not to take a language, but have to face so many exceptions??
`` If the day should ever come that foreign invaders swarm ashore along the Gulf Coast '', the account reads, `` they can count on heavy opposition from a group of commando-trained telephone employees -- all girls.
If there is anything which we can do in the executive branch of the Government to speed up the processes by which we come to decisions on matters on which we must act promptly, that in itself would be a major contribution to the conduct of our affairs.
If the dance teachers of America make it their business to prepare their young charges for the gymnastics that must come some day if our schools are really responsible, we will be that much ahead.
If anything may be predicted in the quicksilver world of retailing, it seems likely that the suburban branch will come to dominate children's clothing ( taking the kid downtown is too much of a production ), household gadgetry and the discount business in big-ticket items.
If this trade should be resumed, the habitants who had come to be farmers or artisans, and soldiers discharged from the army, must be hardened to the severe life of coureurs de bois.
If you find out anything, come on back here and we'll get started on it ''.
If the Orioles are to break their losing streak within the next two days, it will have to be at the expense of the American League champion New York Yankees, who come in here tomorrow for a night game and a single test Sunday afternoon.
If a man totally ignorant of America were to judge our land and its civilization based on Hollywood alone, what conclusions do you think he might come to??
If we try to choose an element from each set, then, because X is infinite, our choice procedure will never come to an end, and consequently, we will never be able to produce a choice function for all of X.
If these allegiances come into conflict, he or she may be guilty of treason against one or both.
If the demands of these two sovereigns upon his duty of allegiance come into conflict, those of the United States have the paramount authority in American law ; likewise, those of the foreign land have paramount authority in their legal system.
If the media agency responsible for the authorized production allows material from fans, what is the limit before legal constraints from actors, music, and other considerations, come into play?
Shortly thereafter, he decided to follow the words of Jesus, who had said: " If you want to be perfect, go, sell what you have and give to the poor, and you will have treasures in heaven ; and come, follow Me.
Captain Manning was heard to scream, " If any of those bastard Huns come up, lads, hit ' em with an oar!
If you come up with an innovation that serves, that resonates with customers, the Internet will allow that innovation to spread dramatically faster than any other technology has enabled a new innovation to be adopted in the history of mankind.
If a stranger entered the circle, he had to do so to the woman's right so as not to come between her and her husband.
If instead the roll is 4, 5, 6, 8, 9, 10 then the come bet will be moved by the base dealer onto a box representing the number the shooter threw.
If the come-bet point is rolled on the come-out roll, the odds do not win but the come bet does and the odds bet is returned ( along with the come bet and its payoff ).
If a 12 is rolled, it is a push ( this is to reverse the natural house advantage: because the don't come bet puts the player in the position of the house, it would otherwise favour the player ).
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