SCENE: A police officer is chewing something fried and toroid, watching a stop sign with characteristic low cunning. He sees a Toyota Yaris approaching the stop sign rather fast. His chewing slows; his eyes narrow. For a few seconds, his line of sight is obstructed by a second car going the same direction as our Yaris, but in a lane nearer to the cop, and (inexplicably) with no stop sign. When the scene clears again, the Yaris is past the stop sign and going approximately the same speed as before. The cop reaches up to switch on his siren.

If you’re a physicist or an unrealized genius, you can predict what happened here:

SCENE: A physicist approaches stop sign. He’s a hard braker on any day (my inference), but today he’s distracted because he has a cold and he’s sneezing. The muscular sneeze contractions first delay, then intensify his foot-press on the brake, and his little Toyota Yaris really slams to a stop. Our physicist is also a fast accelerator, and coming off the line he floors the Yaris, which everyone knows has a sick in-line DOHC four with 103 ft-lbs of dizzizling torque, and in a wink he’s going just as fast as he was when sneezing pre-stop-sign.

RESULT: The physicist gets a ticket.

COOLER RESULT: The physicist writes a paper showing how the cop’s reliance on visual estimate of angular velocity, together with the short length of the Yaris, the long length of the view-obstructing car, his sneeze braking, and his fast acceleration all combined to make it look like he ran the stop sign even though he didn’t.

COOLEST RESULT: The cop and judge are convinced, and the ticket is thrown out. Or as our physicist puts it, “the paper was awarded a special prize of $400 that the author did not have to pay to the state of California.”

Good report/explanation here.

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