The earth moon distance = 3.8 * 10^8 meters(adsbygoogle = window.adsbygoogle || []).push({});

Time for light to reach moon = 1.266 sec.

A laser at the origin on earth pointed at moon rotates .001 radian

with angular speed w = 10 radians/sec.

The arc length distance described on moon ,s= (radians) (radius) =3.8*10^5 meters

The velocity of the point on the moon described by the change in direction of the laser=

v=(w)(radius) =3.8 *10^9 meters/sec

So the time it would take this point to travel on the moon = distance/rate = 1/10^4 sec as well as .001 radian/10 radians/sec at the origin, being the rotation of the laser.

Since the light takes 1.266 second to travel to moon then it does not seem possible for laser light point on moon to exceed c.

For example in this case it took 1/10^4 seconds for direction of laser point to describe the path on the moon but when the laser is in this final position after rotating .001 radian it will take the light 1.266 seconds to travel to moon.

To restate it seems that the actual velocity of the directed laser light point on the moon would not exceed c because of the time lag

from earth to moon in light travel time .

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# Velocity of laser light pt. on moon > c ?

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