Question

For sound waves, the Doppler formula for frequency shift differs slightly between the situations: (i) source at rest; observer moving, and (ii) source moving; observer at rest. The exact Doppler formulas for the case of light waves in a vacuum are, however, strictly identical for these situations. Explain why this should be so. Would you expect the formulas to be strictly identical for the two situations in the case of light traveling in a medium?

Answer 1

Hint: Sound vibrations travel in a wave pattern, and we call these vibrations sound waves. Sound waves move by vibrating objects and these articles vibrate other encompassing items, conveying the sound along. Sound can move through the air, water, or solids, as long as there are particles to bob off of sound waves that exist as varieties of weight in a medium, for example, air.
They are made by the vibration of an article, which causes the air to encompass it to vibrate. The vibrating air at that point makes the human eardrum vibrate, which the mind deciphers as sound.
 Sound is a mechanical wave that results from the to and fro vibration of the particles of the medium through which the sound wave is moving. The movement of the particles is equal (and against corresponding) to the heading of the energy transport. This is the thing that characterizes sound waves in the air as longitudinal waves.

Complete answer:
 No Sound waves can engender just through a medium. The two given circumstances are not logically indistinguishable in light of the fact that the movement of a spectator comparative with a medium is diverse in the two circumstances. Consequently, the Doppler recipes for the two circumstances can't be equivalent.
 If there should be an occurrence of light waves, sound can go in a vacuum. In a vacuum, the over two cases are indistinguishable on the grounds that the speed of light is free of the movement of the spectator and the movement of the source.
 At the point when the light goes in a medium, the over two cases are not indistinguishable on the grounds that the speed of light relies upon the frequency of the medium.

Note: Doppler Effect takes a shot at both light and sound items. For example, when a sound article moves towards you, the recurrence of the sound waves builds, prompting a higher pitch. Then again, in the event that it moves from you, the recurrence of the sound waves diminishes and the pitch descends.