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If a laser is swept across a distant object, the spot of laser light can easily be made to move across the object at a speed greater than c. Similarly, a shadow projected onto a distant object can be made to move across the object faster than c. In neither case does the light travel from the source to the object faster than c, nor does any information travel faster than light.
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If and laser
If the scientific understanding of the properties of lasers were inaccurate, then the laser measurement would be inaccurate but the others would not.
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 testing showed that the central processing unit was working but the FPU was defective, the FPU's power and bus connections were destroyed with a laser and the chip was sold cheaper as an SX ; if the FPU worked it was sold as a DX.
If the applied pump power is too small, the gain will never be sufficient to overcome the resonator losses, and laser light will not be produced.
If the number of photons being amplified per unit time is greater than the number of photons being absorbed, then the net result is a continuously increasing number of photons being produced ; the laser medium is said to have a gain of greater than unity.
If such an Interstellar Internet exists, the hypothesis states, communications between servers are mostly through narrow-band, highly directional radio or laser links.
If the launch fibre is underfilled, for example as a consequence of being energized by a laser diode or edge-emitting LED, there will be no effect on the mode power distribution or loss measurements.
If multimode fiber bandwidth is measured using a laser diode directly coupled to its input, the resulting measurement can vary by as much as an order of magnitude.
If a photographic plate or another 2-D optical sensor is located within the scattered light field without a lens, a speckle pattern is obtained whose characteristics depend on the geometry of the system and the wavelength of the laser.
If the MiniDisc player were bumped, playback could continue unimpeded while the laser repositioned itself to continue reading data from the disc.
If the mole is incompletely removed by the laser, and the pigmented lesion regrows, it might form a recurrent nevus.
If toner spills into the laser printer, a special type of vacuum cleaner with an electrically conductive hose and a high efficiency ( HEPA ) filter may be needed for effective cleaning.
If detected, laser treatment, radiation and surgeries can be used to treat the tumor.
If instead of oscillating independently, each mode operates with a fixed phase between it and the other modes, the laser output behaves quite differently.
If there are N modes locked with a frequency separation Δν, the overall mode-locked bandwidth is NΔν, and the wider this bandwidth, the shorter the pulse duration from the laser.
If the Q factor of a laser's cavity is abruptly changed from a low value to a high one, the laser will emit a pulse of light that is much more intense than the laser's normal continuous output.
If a purchased item does not break the laser beam when falling, the spirals will automatically turn, usually three times to ensure that a product will fall.
If the lesion can be completely removed via surgical resection, cryotherapy, laser ablation, or some other locally-targeted treatment modality before frank invasion and metastasis develops, cure rates for CIS approach 100 %.
If light of a fixed frequency / wavelength / color ( as from a laser ) is assumed, then the time-harmonic ( frequency-domain ) form of the optical field is given as:
If the aircraft detects the targeting laser, it has the whole period of the missile flight time to engage in avoidance maneuvers, which adds additional challenge to the missile operator's target-tracking task.
If laser light is employed, it is possible to selectively excite a molecule so as to produce a desired electronic and vibrational state.
If launched, LISA will be the first dedicated space-based gravitational-wave detector ; it will measure gravitational waves by using laser interferometry to monitor the fluctuations in the relative distances between three spacecraft, arranged in an equilateral triangle with 5 million kilometer arms, and flying along an Earth-like heliocentric orbit.
If the emitted light is of a specific visible wavelength it may be called colorimetry, or it may involve specific wavelength of light e. g. by use of laser and emission of fluorescent signals of another specific wavelength which is detected via very specific wavelength optical filters.
If and is
If the circumstances are faced frankly it is not reasonable to expect this to be true.
If his dancers are sometimes made to look as if they might be creatures from Mars, this is consistent with his intention of placing them in the orbit of another world, a world in which they are freed of their pedestrian identities.
If a work is divided into several large segments, a last-minute drawing of random numbers may determine the order of the segments for any particular performance.
If they avoid the use of the pungent, outlawed four-letter word it is because it is taboo ; ;
If Wilhelm Reich is the Moses who has led them out of the Egypt of sexual slavery, Dylan Thomas is the poet who offers them the Dionysian dialectic of justification for their indulgence in liquor, marijuana, sex, and jazz.
If he is the child of nothingness, if he is the predestined victim of an age of atomic wars, then he will consult only his own organic needs and go beyond good and evil.
If it is an honest feeling, then why should she not yield to it??
If he thus achieves a lyrical, dreamlike, drugged intensity, he pays the price for his indulgence by producing work -- Allen Ginsberg's `` Howl '' is a striking example of this tendency -- that is disoriented, Dionysian but without depth and without Apollonian control.
If love reflects the nature of man, as Ortega Y Gasset believes, if the person in love betrays decisively what he is by his behavior in love, then the writers of the beat generation are creating a new literary genre.
If he is good, he may not be legal ; ;
If the man on the sidewalk is surprised at this question, it has served as an exclamation.
If the existent form is to be retained new factors that reinforce it must be introduced into the situation.
If we remove ourselves for a moment from our time and our infatuation with mental disease, isn't there something absurd about a hero in a novel who is defeated by his infantile neurosis??
If many of the characters in contemporary novels appear to be the bloodless relations of characters in a case history it is because the novelist is often forgetful today that those things that we call character manifest themselves in surface behavior, that the ego is still the executive agency of personality, and that all we know of personality must be discerned through the ego.
If he is a traditionalist, he is an eclectic traditionalist.
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 to be innocent is to be helpless, then I had been -- as are we all -- helpless at the start.
If and swept
If the absorption occurs in the junction's depletion region, or one diffusion length away from it, these carriers are swept from the junction by the built-in field of the depletion region.
( If a wing has a rectangular planform, rather than tapered or swept, then the chord is simply the width of the wing measured in the direction of airflow.
* Tony Palmer, in The Observer, wrote shortly after the album's release: " If there is still any doubt that Lennon and McCartney are the greatest songwriters since Schubert, then ... album The Beatles ... should surely see the last vestiges of cultural snobbery and bourgeois prejudice swept away in a deluge of joyful music making ..."
If so, it was swept away in 781, when Charlemagne had his son renamed as Pippin.
If a swept wing is continuous-an oblique swept wing, the pressure iso-bars will be swept at a continuous angle from tip to tip.
If this happens divers will not want to descend with the buoy and will prefer to release the shot line and be swept away from the shot.
If the Germans had recently swept a particular area for mines, and Bletchley Park was in need of some cribs, they might ( and apparently did on several occasions ) direct that the area be mined again.
If the target aircraft was to one side of the antenna's axis, the system would see the strength of the signal grow and fade as the beam swept across it, allowing the system to move the dish in the direction of the maximum signal and thereby track the target.
If the current cargo is not the same as the residue remaining on the barge deck, the residue should be swept up against the barge coaming and in some cases may be shoveled and placed into a container or bag.
If one rotates a line L around another line L ' skew but not perpendicular to it, the surface of revolution swept out by L is a hyperboloid of one sheet.
' If you are looking for an underrated film noir gem — that somehow got swept under the rug — this is it!
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