The Doppler effect (or Doppler shift), named after Austrian physicist Christian Doppler who proposed it in 1842, is the change in frequency and wavelength of a wave for an observer moving relative to the source of the waves. It is commonly heard when a vehicle sounding a siren approaches, passes and recedes from an observer. The received frequency is increased (compared to the emitted frequency) during the approach, it is identical at the instant of passing by, and it is decreased during the recession. For waves that propagate in a medium, such as sound waves, the velocity of the observer and of the source are relative to the medium in which the waves are transmitted. The total Doppler effect may therefore result from motion of the source, motion of the observer, or motion of the medium. Each of these effects is analyzed separately. For waves which do not require a medium, such as light or gravity in special relativity, only the relative difference in velocity between the observer and the source needs to be considered.
http://en.wikipedia.org/wiki/Doppler_effect
There is an unfortunate optical illusion - a variant on the Doppler effect - that besets all frauds. It's unfortunate, because it has the effect of exacerbating the pecuniary losses that fraud victims endure, by unfairly leaving them, like many rape victims, irrationally ashamed of themselves. The Doppler principle we posit holds that as a victim approaches a swindler, he sees nothing but green lights. But as soon as he realizes that his money is gone, he spins around and beholds, as if by magic, bright red flags as far as the eye can see.
http://money.cnn.com/2009/03/31/news/newsmakers/parloff_dreier.fortune/index4.htm
Some people are smart but in the end lose everything. It's a state of mind.
No comments:
Post a Comment