Forces and Motion

Using physics to avoid speeding tickets

Stories from Physics for 11-14 14-16 IOP RESOURCES

Two students at the University of Leicester published a paper considering whether a car could travel fast enough to be red-shifted out of a speed camera’s field of vision. They concluded that a car would have to travel at the unlikely velocity of 0.178 times the speed of light, a velocity that would cause a Ferrari 458 to contract by just over 7 cm. Dimitri Krioukov deployed a more successful use of physics to avoid punishment after he was pulled over for driving through a stop sign. He posted a paper on ArXiv to explain that the police officer had been taken in by a perceptual illusion. Krioukov claimed that his rapid linear deceleration to a stop followed by acceleration, was mistakenly perceived as movement at approximately constant speed because the police office perceived the angular rather than the linear speed of the car. It is reported that Krioukov did not have to pay the $400 fine.


appears in the relation SUVAT Equations
can be represented by Motion Graphs
has the special case Wave Speed
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