- #1
Terocamo
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I have just read about the principle of Doppler effect.
However there is a point which seemed a bit tricky.
According to the book, when the source of wave is moving the apparent frequency to a stationary observer is given by the equation:
f'=true frequency*speed of wave/(speed of wave + speed of source)
On the other hand, if an observer is moving towards a stationary source, the frequency is given by:
f'=original frequency * (speed of wave - speed of observer)/(speed of wave)
But referring to the basic principle of displacement, the velocity of the observer and that of source is a relative value. So theoretically there is no difference whether is the source moving or the observer moving, because its only relative motion.
However, with respect to the equation, they are not exactly equal (very close though).
What I want to know is the reason behind this or is there something that I missed?
However there is a point which seemed a bit tricky.
According to the book, when the source of wave is moving the apparent frequency to a stationary observer is given by the equation:
f'=true frequency*speed of wave/(speed of wave + speed of source)
On the other hand, if an observer is moving towards a stationary source, the frequency is given by:
f'=original frequency * (speed of wave - speed of observer)/(speed of wave)
But referring to the basic principle of displacement, the velocity of the observer and that of source is a relative value. So theoretically there is no difference whether is the source moving or the observer moving, because its only relative motion.
However, with respect to the equation, they are not exactly equal (very close though).
What I want to know is the reason behind this or is there something that I missed?