Doppler effect ( general equation)

Description

The Doppler effect is the change in frequency of a wave (or other periodic event) for an observer moving relative to its source. When the speeds of source and the receiver relative to the medium are lower than the velocity of waves in the medium, there is a relationship between observed frequency and emitted frequency depended on the velocity of waves in the medium. The velocity of the receiver relative to the medium is positive if the receiver is moving towards the source (and negative in the other direction).
The velocity of the source relative to the medium is positive if the source is moving away from the receiver (and negative in the other direction).

Related formulas

Variables

fThe observed frequency (hz)
f0The emitted frequency (hz)
cVelocity of waves in the medium (m/s)
vrVelocity of the receiver relative to the medium (m/s)
vsVelocity of the source relative to the medium (m/s)