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

Superman is carrying a red lantern with wavelength 650nm. He flies toward you at a speed of 2.7x108 m/s.

What is the observed wavelength?

2. Relevant equations

[itex]f'=\frac{f}{\left(1-\frac{v_s}{v}\right)}[/itex]

and

[itex]f=\frac{c}{\lambda}[/itex]

3. The attempt at a solution

I used the equation [itex]f'=\frac{f}{\left(1-\frac{v_s}{v}\right)}[/itex] and got my answer to be [itex]65[/itex] nm. What did I do wrong?

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# Doppler Effect Source Moving Closer

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