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1) In an earth reference frame, a star is 82 light years away. How fast would you have to travel so that to you the distance would only be 35 light years?

First I have two simple questions:

1. Light years is in a unit of time or length?

2. How to convert light years?

So I would use either:

a) L = Lo x sqroot(1-v^2/c^2) ~~~> 82 light years = 35 light years x sqr(1-v^2/(3.0 x 10^8)^2)

or

b) to = t x sqroot(1-v^2/c^2) ~~~> 35 light years = 85 light years x sqr(1-v^2/(3.0 x 10^8)^2)

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# Homework Help: Problem dealing with a chapter on relativity

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