Einstein said that the laws of physics must be the same for all observers moving at a#constant velovity. Ignoring wind, an arrow shot from a car moving at any speed would look to an observer in the car exactly the same as an arrow shot standing still on the road, by an observer standing on the road. Not sure that helps but its true. </p>
But of course if you shoot Samick extremes you might want to factor in reletivistic effects
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