Question

Doppler shifted hydrogen absorption lines are seen in the spectrum of a star. The hydrogen line at 656.28 nm is seen to be shifted to 656.08 nm. How large is the shift in wavelength

Answer 1

0.2 nm

Step-by-step explanation:

When an object and observer are moving towards each other, the wavelength of light between them reduces.

When an object and observer are moving away from each other, the wavelength of light between them increases.

Here the wavelength has reduced so the objects are moving towards each other.

The shift in the wavelength is
`656.28-656.08=0.2\ nm`