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roberto85
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Homework Statement
The hydra cluster is 900 Mpc (3x10^9 light years) away. Calcium atoms emit a spectral line of wavelength 396.8 nm. This line is observed at 487.5 nm. The velocity of the cluster, v, is given by ([tex]\lambda[/tex] =c/f)
487.5 = 396.8 SQRT((1+v/c)/(1-v/c))
How do i find v please?