Doppler Effect: Speed Relative to Ground, Source, or Listener?

[Bassel]

hi i just want to ask about the formula of Doppler Effect . The speeds of the listener VL and the source Vs are relative to the ground, source, or listener ?

 

[Doc Al]

hi i just want to ask about the formula of Doppler Effect . The speeds of the listener VL and the source Vs are relative to the ground, source, or listener ?

If the air is stationary relative to the ground (no wind to worry about), then the speeds of the listener and source will be relative to the ground.

 

[dauto]

Neither. It is relative to the air.