(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

When the source is not moving, ## \lambda = 6250 A ## .....(1)

When the source is moving, ## \lambda ' = 6500 A ## .....(2)

From (1) and (2),

## \lambda ' > \lambda ## .....(3)

This means that the source is moving away from the Earth.

## \nu ' = \nu \sqrt{ \frac { c+v}{c-v} ##

## {\frac { \lambda }{\lambda '} }^2 = { \frac { c+v}{c-v} ##

0.9245c –c = v(1+0.9245)

V =11760 km/s

Is this correct?

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# Doppler effect: calculate speed of a moving star

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