>>>And something similar from everyday life.
>>>One day the speed of bypassing car might be measured with a ruler and a clock. The next day, if the same measurement gave a different answer, no one could tell if the speed of the car changed, the ruler length changed, or the clock ticking changed, or your car is moving differently, or your eyes became older.
>>>
>>>So what is here relativity for?
>>>
>>>>One day the speed of light might be measured with a ruler and a clock. The next day, if the same measurement gave a different answer, no one could tell if the speed of light changed, the ruler length changed, or the clock ticking changed.
>>
>>But here Cop's radar always is right :o)
>
>Radar works at the speed of the electro-magnetic spectrum too.

Yes, maybe Radar is not the correct word, I mean these devices that cops used when they measured car speed.
no metter what you said, cops are always right, so their devices are the standard for car speed :o)