Radiotelescopes are designed to observe 21-cm wavesemitted
Chapter 44, Problem 44.30(choose chapter or problem)
Radiotelescopes are designed to observe 21-cm wavesemitted by atomic hydrogen gas. A signal from a distantradio-emitting galaxy is found to have a wavelength that is0.10 cm longer than the normal 21-cm wavelength. Estimatethe distance to this galaxy.
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