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insipiens
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Homework Statement
If a spacecraft is traveling to a star which is located at a distance of 1 lightyear and it would take the spacecraft 1 year to reach the star in its own frame, how fast would the spacecraft actually fly? Also, how long would the journey take for an observer on Earth (t_e)?
t_sc = 1 y
L_e = 1 ly
t_e = ?
Homework Equations
gamma = 1/sqrt(1-v^2/c^2)
beta = v^2/c^2
t_sc = t_e / gamma
L_sc = L_e /gamma
The Attempt at a Solution
I would start by saying that the L_e = v * t_e (v = the velocity). After throwing everything around, I get that the speed should be 25% of the speed of light, which I don't actually think is correct.
My calculations so far:
L_e = t_e * v = t_sc *v *gamma
L_e / t_sc = c = v * gamma
1/gamma^2 = beta^2
1-beta^2 = beta^2 --> beta = 1/4
Hence the time on Earth should be 4 years.
Thanks for everyone willing to help me!
Cheers,
Merlin