Question

A wavelength in the middle of visible spectrum will be shifted
towards red when the source and the observer move away from
each other. This is due to
(a) interference of light
(b) dispersion of light
le) polarisation of light
(d) Doppler effect in light

Answer 1

interference of light

Answer 2

Answer:

Doppler effect.

Explanation:

Since here the question is about the shifting of the wavelength then the theory of Doppler effect comes into use. The shift in the wavelength implies the shift in the frequency which means that the  longer the wavelength of the light will have shorter frequency and the shorter wavelength of the light will have longer frequency.

We know this from the  Doppler effect that when the source moves towards the observer any waves that are emitted which is measure are shifted to shorter wavelengths  which is known as the blueshift . While if the source moves away from the observer, the shift will be for the longer wavelengths  which is known as the redshift.