>>>>>
>>>>>
>>>>>What is it that revolves on the roof of a police car?
>>>>
>>>>Nothing.
>>>
>>>How so? What about when the cruiser's blue and red lights are on>
>>
>>On american police cars everything is fixed to the roof and nothing revolves on the roof.
>
>So how do the lights describe a circle?


You old worlders use outdated technology. Why use mechanical devices that *rotate* a light? What are they, rolling lighthouses? So 20th century.

We use quarz crystals that oscillante in a precise frequency to show a rotating-blinking effect and to numb the brains of gullible non-technical people into thinking they are actually rotating colorful lights.