Answer:
[tex]\lambda_o=133.4994\ cm[/tex]
Explanation:
Given:
speed of light source towards the earth, [tex]v=7.045\times 10^5\ m.s^{-1}[/tex]
wavelength of the light emitted by the source, [tex]\lambda_s=133.5\ cm[/tex]
We know the speed of electromagnetic waves is, [tex]c=3\times10^8\ m.s^{-1}[/tex]
Here since the speed of the source is comparable to the speed of light, we've:
For the doppler effect of EM waves:
[tex]\frac{\lambda_o}{\lambda_s} =\sqrt{(1-\frac{v}{c} )\div(1+\frac{v}{c} )}[/tex]
[tex]\frac{\lambda_o}{133.5}=\sqrt{(1-\frac{7.045\times 10^5}{3\times10^8})\div (1+\frac{7.045\times 10^5}{3\times10^8})}[/tex]
[tex]\lambda_o=133.4994\ cm[/tex]
