Answer:of
Astronomers living on planets a measure λO = 3.80_nm
Astronomers living on planets b measure λO = 4.2_nm
Step-by-step explanation:
Astronomers living on planets a measure λO = 3.80_nm
Astronomers living on planets b measure λO = 4.2_nm
a.) Speed of the radio wave
c = 299792458 m/s.
λO = λS(c − vS)/(c − vO)
λO = observed wavelength
λS = source constant wavelength = 4 nm
c = wavefront constant velocity = 299792458 m/s
vS = velocity of the source = 15000 km/s
vO = velocity of the observer 0