- #1

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## Homework Statement

So basically I'm given the distance to the moon (384,000,000 meters), and I need to find out how many degrees per second I'd need to move the laser for the spot touching the moon to move faster than the speed of light.

## Homework Equations

[itex]w=\frac{v}{r}[/itex]

## The Attempt at a Solution

I have two ways of doing this and they both give me different answers.

The easy way I thought of would be to make a right triangle with the x being the distance to the moon, and the y being the distance light travels in a second. Then finding the angle of such a triangle gave me [itex]\frac{299,792,458}{384,000,000}=tanθ[/itex], and then I took the inverse tangent to find the angle, which is 38°. So the answer would be 38° per second I'd have to move the laser for the end of the beam to move faster than the speed of light. Well, I'd have to move it any amount greater than that to break the light barrier.

The other way I used angular velocity, which is [itex]w=\frac{v}{r}=\frac{299,792,458}{384,000,000}=0.78[/itex] radians per second, and then I multiply that by 57.3 to turn it into degrees, which gives me 44.8° per second. One of these is wrong. Possibly both. Any suggestions?

Thanks.