Chapter 16.2, Problem 20SSC

To determine

To Describe:The relative motions of objects when light is redshifted and blueshifted in term Doppler Effect.

Explanation of Solution

Introduction:

When the direction of the waves is towards us, the apparent wavelength decreases a little.If it’s the waves of visible light, light colors may change significantly.When wavelength reduces, they change towards the blue end of the spectrum. Astronomers call this a blueshift.When the source moves away from us and the wavelength is longer, it’s a redshift of the light.

When analyzing a two-star system you can tell which one is moving towards you and which one is moving away by observing how the frequencies/wavelengths show variation using the Doppler effect. Doppler Effect equation can be used to calculate the radial velocity of an object.For this calculation, we have to know three parametersa) the speed of the light, b) the original wavelength of the light emitted and c) the difference between the wavelength of the light emitted and the wavelength we observe.