The Doppler Shift Method for Calculating Recession Speed

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The discussion revolves around using the Doppler Shift method to calculate recession speed, specifically addressing the lack of provided wavelength in the homework question. Participants suggest calculating the Doppler shift by taking the difference between the maximum and minimum wavelengths in the visible spectrum, from 6600 angstroms to 3900 angstroms. The formula v/c = Δλ/λ is referenced to determine the recession speed. It is recommended to use the actual wavelength of UV light (3900 angstroms) for accurate results. The conversation emphasizes the importance of correctly applying the Doppler shift formula to obtain the recession speed.
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Homework Statement

see attachment

Homework Equations


The Attempt at a Solution



Now the question did not say what the wavelength was which is annoying.
BUT would this be a good way to work it out?

\frac {v}{c} = \frac{Δλ}{λ}
 

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i think u r right somewhat. calculate the doppler shift of the wavelength as the entire range of visible region, i.e, 6600 angstorm minus 3900 angstorm. use the doppler shift of wavelength'' formula and get the actual speed of receeding. the actual wave length would be of UV (3900 angstorm). try this and tally the ans.
 
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