In a laboratory, the Balmer beta line has a wavelength of 486.1 nm. If the line appears in a star's spectrum at 485.0 nm.
Is it approaching or receding? And i would like to know why
Is it approaching or receding? And i would like to know why
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The star is approaching since the wavelength of the Balmer line in the star's spectrum is shorter than the rest Balmer line.
The star's velocity is found from
v = c(∆λ/λo)
v = (3 x 10^5) (486.1 - 485)/486.1 = 678.9 km per second
The star's velocity is found from
v = c(∆λ/λo)
v = (3 x 10^5) (486.1 - 485)/486.1 = 678.9 km per second
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I have no idea I just need the two points