Hello brainy people,(adsbygoogle = window.adsbygoogle || []).push({});

I did solve this problem, but my answer is double the correct one, I wonder what went wrong.

here it is:

The Lyman alpha spectral line of hydrogen (lambda = 122 nm) differs by 1.8*10^-12 m in spectra taken at opposite ends of the sun's equator. What is the speed of a particle on the equator due to the Sun's rotation, in kilometers per second?

I used the doppler formula, delta lambda/lambda = v/c

so I got c = 4.4 Km/s, but the correct answer is 2.2 km/s

thanks for your effort

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Gre Problem # 60

**Physics Forums | Science Articles, Homework Help, Discussion**