Assume that the sun rotates about an axis through its centre and perpendicular to the plane of rotation of the earth about the sun. The appearance of the sun, from any one point on the earth, is shown. Light belonging to a particular spectral line, as received from the points A, B, C and D on the edge of the sun, are analyzed :

Question

Assume that the sun rotates about an axis through its centre and perpendicular to the plane of rotation of the earth about the sun. The appearance of the sun, from any one point on the earth, is shown. Light belonging to a particular spectral line, as received from the points A, B, C and D on the edge of the sun, are analyzed : (A) Light from all four points have the same wavelength (B) Light from C has greater wavelength than the light from D (C) Light from D has greater wavelength than the light from C (D) Light from A has the same wavelength as the light from B

Tardigrade Admin · Accepted Answer

As point D is moving awave from earth the light from this point will have a greater wavelength and point C is moving toward earth, light from this point will have a short wavelength. point A and B are at rest in the observer's frame so light from both of these points will have same wavelength.