Multiple Choice
We are measuring the spectra of two hydrogen gas clouds. The laboratory frame wavelength of one hydrogen line is 656.2 nm. Cloud A's emission line wavelength is 660.1 nm and Cloud B's emission line wavelength is 670.1 nm. What can we conclude about these clouds?
A) They are both approaching us, and Cloud A is approaching faster than Cloud B.
B) They are both approaching us, and Cloud B is approaching faster than Cloud A.
C) They are both receding from us, and Cloud A is receding faster than Cloud B.
D) They are both receding from us, and Cloud B is receding faster than Cloud A.
Correct Answer:

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Correct Answer:
Verified
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