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If a quasar has a redshift of 3.3, at what fraction of the speed of light is it moving away from us?

User Qnan
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1 Answer

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Answer:

The quasar is moving with 0.68 the speed of light.

Step-by-step explanation:

let v be the speed quasar is moving with away from us, z be the redshift and c be the speed of light.

Using the relativistic doppler shift formula, the fraction of the speed of light that the quasar is moving away from us is given by:

v/c = [(z - 1)^2 -1]/[(z - 1)^2 + 1]

= [(3.3 - 1)^2 -1]/[(3.3 - 1)^2 + 1]

= 0.68

Therefore, the quasar is moving with 0.68 the speed of light.

User ISensical
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